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72-471: The name of this protein family is derived from a mutant phenotype resulting from mutation of AGO1 in Arabidopsis thaliana , which was likened by Bohmert et al. to the appearance of the pelagic octopus Argonauta argo . RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression , via either destruction of specific mRNA molecules or suppressing translation. RNAi has

144-495: A corymb ; their structure is that of the typical Brassicaceae . The fruit is a siliqua 5–20 mm long, containing 20–30 seeds . Roots are simple in structure, with a single primary root that grows vertically downward, later producing smaller lateral roots. These roots form interactions with rhizosphere bacteria such as Bacillus megaterium . A. thaliana can complete its entire lifecycle in six weeks. The central stem that produces flowers grows after about 3 weeks, and

216-401: A homeodomain and Blazquez et al 2001 that fve produces a WD40 repeat . The UVR8 protein detects UV-B light and mediates the response to this DNA-damaging wavelength. A. thaliana was used extensively in the study of the genetic basis of phototropism , chloroplast alignment, and stomal aperture and other blue light-influenced processes. These traits respond to blue light, which

288-410: A C-terminal PIWI domain. The PAZ domain is named for Drosophila Piwi, Arabidopsis Argonaute-1, and Arabidopsis Zwille (also known as pinhead, and later renamed argonaute-10), where the domain was first recognized to be conserved. The PAZ domain is an RNA binding module that recognizes single-stranded 3′ ends of siRNA , miRNA and piRNA , in a sequence independent manner. PIWI is named after

360-498: A display of phenotypic plasticity . On January 2, 2019, China's Chang'e-4 lander brought A. thaliana to the moon. A small microcosm 'tin' in the lander contained A. thaliana , seeds of potatoes, and silkworm eggs. As plants would support the silkworms with oxygen, and the silkworms would in turn provide the plants with necessary carbon dioxide and nutrients through their waste, researchers will evaluate whether plants successfully perform photosynthesis , and grow and bloom in

432-401: A model for flower development. The developing flower has four basic organs - sepals , petals , stamens , and carpels (which go on to form pistils ). These organs are arranged in a series of whorls, four sepals on the outer whorl, followed by four petals inside this, six stamens, and a central carpel region. Homeotic mutations in A. thaliana result in the change of one organ to another—in

504-535: A potentially evolutionarily ancient mechanism for protecting organisms from viruses. The small interfering RNAs produced by Dicer cause sequence specific, post-transcriptional gene silencing by guiding an endonuclease, the RNA-induced silencing complex (RISC), to mRNA. This process has been seen in a wide range of organisms, such as Neurospora fungus (in which it is known as quelling), plants (post-transcriptional gene silencing) and mammalian cells(RNAi). If there

576-444: A powerful tool for the study of the subdiscipline of plant pathology , that is, the interaction between plants and disease-causing pathogens . The use of A. thaliana has led to many breakthroughs in the advancement of knowledge of how plants manifest plant disease resistance . The reason most plants are resistant to most pathogens is through nonhost resistance - not all pathogens will infect all plants. An example where A. thaliana

648-403: A relatively small genome of around 135 megabase pairs . It was the first plant to have its genome sequenced, and is an important tool for understanding the molecular biology of many plant traits, including flower development and light sensing . Arabidopsis thaliana is an annual (rarely biennial ) plant, usually growing to 20–25 cm tall. The leaves form a rosette at the base of

720-401: A significant role in defending cells against parasitic nucleotide sequences . In eukaryotes, including animals, RNAi is initiated by the enzyme Dicer . Dicer cleaves long double-stranded RNA (dsRNA, often found in viruses and small interfering RNA ) molecules into short double stranded fragments of around 20 nucleotide siRNAs. The dsRNA is then separated into two single-stranded RNAs (ssRNA) –

792-463: Is 367,808 base pairs long and contains 57 genes. There are many repeated regions in the Arabidopsis mitochondrial genome. The largest repeats recombine regularly and isomerize the genome. Like most plant mitochondrial genomes, the Arabidopsis mitochondrial genome exists as a complex arrangement of overlapping branched and linear molecules in vivo . Genetic transformation of A. thaliana

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864-587: Is a complete or near complete sequence complementarity between the small RNA and the target, the Argonaute protein component of RISC mediates cleavage of the target transcript, the mechanism involves repression of translation predominantly. In 2016, a group from Hebei University of Science and Technology reported genome editing using a prokaryotic Argonaute protein from Natronobacterium gregoryi . However, evidence for application of Argonaute proteins as DNA-guided nucleases for genome editing have been questioned, with

936-526: Is another example of resistance that is better understood in plants because of research done in A. thaliana . Benzothiadiazol (BTH), a salicylic acid (SA) analog, has been used historically as an antifungal compound in crop plants. BTH, as well as SA, has been shown to induce SAR in plants. The initiation of the SAR pathway was first demonstrated in A. thaliana in which increased SA levels are recognized by nonexpresser of PR genes 1 ( NPR1 ) due to redox change in

1008-603: Is delivered into A. thaliana via the Type III secretion system of P. syringae pv. tomato strain DC3000 . Recognition of avrRpt2 by RPS2 occurs via the guardee protein RIN4, which is cleaved. Recognition of a pathogen effector leads to a dramatic immune response known as the hypersensitive response , in which the infected plant cells undergo cell death to prevent the spread of the pathogen. Systemic acquired resistance (SAR)

1080-420: Is edible by humans in a salad or cooked, but it does not enjoy widespread use as a spring vegetable. Botanists and biologists began to research A. thaliana in the early 1900s, and the first systematic description of mutants was done around 1945. A. thaliana is now widely used for studying plant sciences , including genetics , evolution , population genetics, and plant development. Although A. thaliana

1152-399: Is generally applicable to other flowering plants. Studies of A. thaliana have provided considerable insights with regards to the genetics of leaf morphogenesis, particularly in dicotyledon-type plants. Much of the understanding has come from analyzing mutants in leaf development, some of which were identified in the 1960s, but were not analysed with genetic and molecular techniques until

1224-553: Is known as the guide strand, which is incorporated into the Argonaute protein and leads gene silencing. The other single-stranded RNA, named the passenger strand, is degraded during the RNA-induced silencing complex process. Once the Argonaute is associated with the small RNA, the enzymatic activity conferred by the PIWI domain cleaves only the passenger strand of the small interfering RNA. RNA strand separation and incorporation into

1296-797: Is likely only poorly understood and only known in general terms (e.g. as "DNA-binding protein without known specificity"). Uniprot lists more than 3,000 proteins as "uncharacterized" as part of the reference proteome. The plastome of A. thaliana is a 154,478 base-pair-long DNA molecule, a size typically encountered in most flowering plants (see the list of sequenced plastomes ). It comprises 136 genes coding for small subunit ribosomal proteins ( rps , in yellow: see figure), large subunit ribosomal proteins ( rpl , orange), hypothetical chloroplast open reading frame proteins ( ycf , lemon), proteins involved in photosynthetic reactions (green) or in other functions (red), ribosomal RNAs ( rrn , blue), and transfer RNAs ( trn , black). The mitochondrial genome of A. thaliana

1368-515: Is perceived by the phototropin light receptors. Arabidopsis has also been important in understanding the functions of another blue light receptor, cryptochrome , which is especially important for light entrainment to control the plants' circadian rhythms . When the onset of darkness is unusually early, A. thaliana reduces its metabolism of starch by an amount that effectively requires division . Light responses were even found in roots, previously thought to be largely insensitive to light. While

1440-606: Is probably essential to Golgi - vacuole trafficking. This is still a wide open field and plant SNAREs' role in trafficking remains understudied. The DNA of plants is vulnerable to ultraviolet light, and DNA repair mechanisms have evolved to avoid or repair genome damage caused by UV. Kaiser et al. showed that in A. thaliana cyclobutane pyrimidine dimers (CPDs) induced by UV light can be repaired by expression of CPD photolyase . On May 12, 2022, NASA announced that specimens of Arabidopsis thaliana had been successfully germinated and grown in samples of lunar regolith . While

1512-552: Is regulated by miRNA itself. AGO4 does not involve in RNAi directed RNA degradation, but in DNA methylation and other epigenetic regulation, through small RNA (smRNA) pathway. AGO10 is involved in plant development. AGO7 has a function distinct from AGO 1 and 10, and is not found in gene silencing induced by transgenes. Instead, it is related to developmental timing in plants. Argonaute proteins were reported to be associated with cancers. For

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1584-431: Is routine, using Agrobacterium tumefaciens to transfer DNA into the plant genome. The current protocol, termed "floral dip", involves simply dipping flowers into a solution containing Agrobacterium carrying a plasmid of interest and a detergent. This method avoids the need for tissue culture or plant regeneration. The A. thaliana gene knockout collections are a unique resource for plant biology made possible by

1656-557: The A. thaliana genome is maintained by the Arabidopsis Information Resource. The genome encodes ~27,600 protein -coding genes and about 6,500 non-coding genes. However, the Uniprot database lists 39,342 proteins in their Arabidopsis reference proteome. Among the 27,600 protein-coding genes 25,402 (91.8%) are now annotated with "meaningful" product names, although a large fraction of these proteins

1728-532: The A. thaliana research community dates to a newsletter called Arabidopsis Information Service, established in 1964. The first International Arabidopsis Conference was held in 1965, in Göttingen , Germany. In the 1980s, A. thaliana started to become widely used in plant research laboratories around the world. It was one of several candidates that included maize, petunia , and tobacco. The latter two were attractive, since they were easily transformable with

1800-433: The gravitropic response of A. thaliana root organs is their predominant tropic response, specimens treated with mutagens and selected for the absence of gravitropic action showed negative phototropic response to blue or white light, and positive response to red light, indicating that the roots also show positive phototropism. In 2000, Dr. Janet Braam of Rice University genetically engineered A. thaliana to glow in

1872-423: The mitogen-activated protein kinase (MAP kinase) cascade. Downstream responses of PTI include callose deposition, the oxidative burst , and transcription of defense-related genes. PTI is able to combat pathogens in a nonspecific manner. A stronger and more specific response in plants is that of effector-triggered immunity (ETI), which is dependent upon the recognition of pathogen effectors, proteins secreted by

1944-442: The thale cress , mouse-ear cress or arabidopsis , is a small plant from the mustard family ( Brassicaceae ), native to Eurasia and Africa. Commonly found along the shoulders of roads and in disturbed land, it is generally considered a weed. A winter annual with a relatively short lifecycle, A. thaliana is a popular model organism in plant biology and genetics. For a complex multicellular eukaryote , A. thaliana has

2016-415: The 17th century. A. thaliana readily grows and often pioneers rocky, sandy, and calcareous soils. It is generally considered a weed, due to its widespread distribution in agricultural fields, roadsides, railway lines, waste ground, and other disturbed habitats, but due to its limited competitive ability and small size, it is not categorized as a noxious weed. Like most Brassicaceae species, A. thaliana

2088-463: The Argonaute protein are guided by the strength of the hydrogen bond interaction at the 5′-ends of the RNA duplex, known as the asymmetry rule. Also the degree of complementarity between the two strands of the intermediate RNA duplex defines how the miRNA are sorted into different types of Argonaute proteins. In animals, Argonaute associated with miRNA binds to the 3′-untranslated region of mRNA and prevents

2160-520: The Drosophila Piwi protein. Structurally resembling RNaseH, the PIWI domain is essential for the target cleavage. The active site with aspartate–aspartate–glutamate triad harbors a divalent metal ion, necessary for the catalysis. Family members of AGO that lost this conserved feature during evolution lack the cleavage activity. In human AGO, the PIWI motif also mediates protein-protein interaction at

2232-780: The L er collection of mutants is derived from this initial line, L er -0 does not correspond to the Landsberg accessions, which designated La-0, La-1, etc. Trichome formation is initiated by the GLABROUS1 protein. Knockouts of the corresponding gene lead to glabrous plants. This phenotype has already been used in gene editing experiments and might be of interest as visual marker for plant research to improve gene editing methods such as CRISPR/Cas9. In 2005, scientists at Purdue University proposed that A. thaliana possessed an alternative to previously known mechanisms of DNA repair , producing an unusual pattern of inheritance , but

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2304-741: The PIWI box, where it binds to Dicer at an RNase III domain. At the interface of PIWI and Mid domains sits the 5′ phosphate of a siRNA, miRNA or piRNA, which is found essential in the functionality. Within Mid lies a MC motif, a homologue structure proposed to mimic the cap-binding structure motif found in eIF4E. It was later found that the MC motif is not involved in mRNA cap binding In humans, there are eight AGO family members, some of which are investigated intensively. However, even though AGO1–4 are capable of loading miRNA, endonuclease activity and thus RNAi-dependent gene silencing exclusively belongs to AGO2. Considering

2376-418: The accumulation of SA for its expression Endogenous Endogeny , in biology, refers to the property of originating or developing from within an organism , tissue , or cell . For example, endogenous substances , and endogenous processes are those that originate from within a living system (e.g., organism , cell ). For instance, estradiol is an endogenous estrogen hormone produced within

2448-592: The adaptation of this species to different environments. A. thaliana is native to Europe, Asia, and Africa, and its geographic distribution is rather continuous from the Mediterranean to Scandinavia and Spain to Greece . It also appears to be native in tropical alpine ecosystems in Africa and perhaps South Africa. It has been introduced and naturalized worldwide, including in North America around

2520-604: The availability of high-throughput transformation and funding for genomics resources. The site of T-DNA insertions has been determined for over 300,000 independent transgenic lines, with the information and seeds accessible through online T-DNA databases. Through these collections, insertional mutants are available for most genes in A. thaliana . Characterized accessions and mutant lines of A. thaliana serve as experimental material in laboratory studies. The most commonly used background lines are L er (Landsberg erecta ), and Col, or Columbia. Other background lines less-often cited in

2592-635: The biological functions of miRNAs are not fully understood, the roles for miRNAs in the coordination of cell proliferation and cell death during development and metabolism have been uncovered. It is trusted that the miRNAs can direct negative or positive regulation at different levels, which depends on the specific miRNAs and target base pair interaction and the cofactors that recognize them. Because it has been widely known that many viruses have RNA rather than DNA as their genetic material and go through at least one stage in their life cycle when they make double-stranded RNA, RNA interference has been considered to be

2664-804: The case of the agamous mutation, for example, stamens become petals and carpels are replaced with a new flower, resulting in a recursively repeated sepal-petal-petal pattern. Observations of homeotic mutations led to the formulation of the ABC model of flower development by E. Coen and E. Meyerowitz . According to this model, floral organ identity genes are divided into three classes - class A genes (which affect sepals and petals), class B genes (which affect petals and stamens), and class C genes (which affect stamens and carpels). These genes code for transcription factors that combine to cause tissue specification in their respective regions during development. Although developed through study of A. thaliana flowers, this model

2736-453: The chromosome number in 1907) did not propose A. thaliana as a model organism, though, until 1943. His student, Erna Reinholz, published her thesis on A. thaliana in 1945, describing the first collection of A. thaliana mutants that they generated using X-ray mutagenesis . Laibach continued his important contributions to A. thaliana research by collecting a large number of accessions (often questionably referred to as " ecotypes "). With

2808-425: The core of RNA-induced silencing complex. Argonaute proteins are the active part of RNA-induced silencing complex, cleaving the target mRNA strand complementary to their bound siRNA. Theoretically the dicer produces short double-stranded fragments so there should be also two functional single-stranded siRNA produced. But only one of the two single-stranded RNA here will be utilized to base pair with target mRNA . It

2880-497: The cytosol, resulting in the reduction of NPR1. NPR1 , which usually exists in a multiplex (oligomeric) state, becomes monomeric (a single unit) upon reduction. When NPR1 becomes monomeric, it translocates to the nucleus, where it interacts with many TGA transcription factors , and is able to induce pathogen-related genes such as PR1 . Another example of SAR would be the research done with transgenic tobacco plants, which express bacterial salicylate hydroxylase, nahG gene, requires

2952-683: The dark when touched. The effect was visible to ultrasensitive cameras. Multiple efforts, including the Glowing Plant project , have sought to use A. thaliana to increase plant luminescence intensity towards commercially viable levels. In 1990, Janet Braam and Ronald W. Davis determined that A. thaliana exhibits thigmomorphogenesis in response to wind, rain and touch. Four or more touch induced genes in A. thaliana were found to be regulated by such stimuli. In 2002, Massimo Pigliucci found that A. thaliana developed different patterns of branching in response to sustained exposure to wind,

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3024-436: The disease process. The PEN genes were later mapped to identify the genes responsible for nonhost resistance to B. graminis . In general, when a plant is exposed to a pathogen, or nonpathogenic microbe, an initial response, known as PAMP-triggered immunity (PTI), occurs because the plant detects conserved motifs known as pathogen-associated molecular patterns (PAMPs). These PAMPs are detected by specialized receptors in

3096-516: The diseases that are involved with selective or elevated expression of particular identified genes, such as pancreatic cancer, the high sequence specificity of RNA interference might make it suitable to be a suitable treatment, particularly appropriate for combating cancers associated with mutated endogenous gene sequences. It has been reported several tiny non-coding RNAs(microRNAs) are related with human cancers, like miR-15a and miR-16a are frequently deleted and/or down-regulated in patients. Even though

3168-517: The flowers naturally self-pollinate. In the lab, A. thaliana may be grown in Petri plates, pots, or hydroponics, under fluorescent lights or in a greenhouse. The plant was first described in 1577 in the Harz Mountains by Johannes Thal  [ de ] (1542–1583), a physician from Nordhausen , Thüringen , Germany, who called it Pilosella siliquosa . In 1753, Carl Linnaeus renamed

3240-435: The function of these receptors has helped plant biologists understand the signaling cascades that regulate photoperiodism , germination , de-etiolation , and shade avoidance in plants. The genes FCA , fy , fpa , LUMINIDEPENDENS ( ld ), fly , fve and FLOWERING LOCUS C ( FLC ) are involved in photoperiod triggering of flowering and vernalization . Specifically Lee et al 1994 find ld produces

3312-492: The growing of polypeptides. In plants, once de novo double-stranded (ds) RNA duplexes are generated with the target mRNA, an unknown RNase-III-like enzyme produces new siRNAs, which are then loaded onto the Argonaute proteins containing PIWI domains, lacking the catalytic amino acid residues, which might induce another level of specific gene silencing. The Argonaute (AGO) gene family encodes six characteristic domains: N- terminal (N), Linker-1 (L1), PAZ, Linker-2 (L2), Mid, and

3384-429: The help of Albert Kranz, these were organised into a large collection of 750 natural accessions of A. thaliana from around the world. In the 1950s and 1960s, John Langridge and George Rédei played an important role in establishing A. thaliana as a useful organism for biological laboratory experiments. Rédei wrote several scholarly reviews instrumental in introducing the model to the scientific community. The start of

3456-400: The host known as pattern recognition receptors (PRRs) on the plant cell surface. The best-characterized PRR in A. thaliana is FLS2 (Flagellin-Sensing2), which recognizes bacterial flagellin , a specialized organelle used by microorganisms for the purpose of motility, as well as the ligand flg22, which comprises the 22 amino acids recognized by FLS2. Discovery of FLS2 was facilitated by

3528-447: The identification of an A. thaliana ecotype, Ws-0, that was unable to detect flg22, leading to the identification of the gene encoding FLS2. FLS2 shows striking similarity to rice XA21, the first PRR isolated in 1995 . Both flagellin and UV-C act similarly to increase homologous recombination in A. thaliana , as demonstrated by Molinier et al. 2006. Beyond this somatic effect, they found this to extend to subsequent generations of

3600-620: The levels of gibberellin increase and leaf primordium initiate growth. The establishment of leaf dorsiventrality is important since the dorsal (adaxial) surface of the leaf is different from the ventral (abaxial) surface. A. thaliana is well suited for light microscopy analysis. Young seedlings on the whole, and their roots in particular, are relatively translucent. This, together with their small size, facilitates live cell imaging using both fluorescence and confocal laser scanning microscopy . By wet-mounting seedlings in water or in culture media, plants may be imaged uninvasively, obviating

3672-570: The lunar environment. Thalianin is an Arabidopsis root triterpene . Potter et al. , 2018 finds synthesis is induced by a combination of at least 2 facts, cell-specific transcription factors (TFs) and the accessibility of the chromatin . Understanding how plants achieve resistance is important to protect the world's food production, and the agriculture industry. Many model systems have been developed to better understand interactions between plants and bacterial , fungal , oomycete , viral , and nematode pathogens. A. thaliana has been

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3744-422: The mid-1990s. A. thaliana leaves are well suited to studies of leaf development because they are relatively simple and stable. Using A. thaliana , the genetics behind leaf shape development have become more clear and have been broken down into three stages: The initiation of the leaf primordium , the establishment of dorsiventrality , and the development of a marginal meristem . Leaf primordia are initiated by

3816-447: The need for fixation and sectioning and allowing time-lapse measurements. Fluorescent protein constructs can be introduced through transformation . The developmental stage of each cell can be inferred from its location in the plant or by using fluorescent protein markers , allowing detailed developmental analysis . The photoreceptors phytochromes A, B, C, D, and E mediate red light-based phototropic response. Understanding

3888-407: The passenger strand and the guide strand. Subsequently, the passenger strand is degraded, while the guide strand is incorporated into the RNA-induced silencing complex (RISC). The most well-studied outcome of the RNAi is post-transcriptional gene silencing, which occurs when the guide strand pairs with a complementary sequence in a messenger RNA molecule and induces cleavage by Argonaute, that lies in

3960-445: The pathogen that alter functions in the host, by plant resistance genes (R-genes) , often described as a gene-for-gene relationship . This recognition may occur directly or indirectly via a guardee protein in a hypothesis known as the guard hypothesis . The first R-gene cloned in A. thaliana was RPS2 (resistance to Pseudomonas syringae 2), which is responsible for recognition of the effector avrRpt2. The bacterial effector avrRpt2

4032-512: The phenomenon observed (reversion of mutant copies of the HOTHEAD gene to a wild-type state) was later suggested to be an artifact because the mutants show increased outcrossing due to organ fusion. The plant's small size and rapid lifecycle are also advantageous for research. Having specialized as a spring ephemeral , it has been used to found several laboratory strains that take about 6 weeks from germination to mature seed. The small size of

4104-532: The plant Arabis thaliana in honor of Thal. In 1842, German botanist Gustav Heynhold erected the new genus Arabidopsis and placed the plant in that genus. The generic name, Arabidopsis , comes from Greek , meaning "resembling Arabis " (the genus in which Linnaeus had initially placed it). Thousands of natural inbred accessions of A. thaliana have been collected from throughout its natural and introduced range. These accessions exhibit considerable genetic and phenotypic variation, which can be used to study

4176-456: The plant . A second PRR, EF-Tu receptor (EFR), identified in A. thaliana , recognizes the bacterial EF-Tu protein, the prokaryotic elongation factor used in protein synthesis , as well as the laboratory-used ligand elf18. Using Agrobacterium -mediated transformation , a technique that takes advantage of the natural process by which Agrobacterium transfers genes into host plants, the EFR gene

4248-433: The plant has little direct significance for agriculture, A. thaliana the model organism has revolutionized our understanding of the genetic, cellular, and molecular biology of flowering plants. The first mutant in A. thaliana was documented in 1873 by Alexander Braun , describing a double flower phenotype (the mutated gene was likely Agamous , cloned and characterized in 1990). Friedrich Laibach (who had published

4320-516: The plant is convenient for cultivation in a small space, and it produces many seeds. Further, the selfing nature of this plant assists genetic experiments. Also, as an individual plant can produce several thousand seeds, each of the above criteria leads to A. thaliana being valued as a genetic model organism. Arabidopsis is often the model for study of SNAREs in plants . This has shown SNAREs to be heavily involved in vesicle trafficking . Zheng et al. 1999 found an Arabidopsis SNARE called AtVTI1a

4392-400: The plant, with a few leaves also on the flowering stem . The basal leaves are green to slightly purplish in color, 1.5–5 cm long, and 2–10 mm broad, with an entire to coarsely serrated margin; the stem leaves are smaller and unstalked, usually with an entire margin. Leaves are covered with small, unicellular hairs called trichomes . The flowers are 3 mm in diameter, arranged in

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4464-489: The plants successfully germinated and grew into seedlings, they were not as robust as specimens that had been grown in volcanic ash as a control group, although the experiments also found some variation in the plants grown in regolith based on the location the samples were taken from, as A. thaliana grown in regolith gathered during Apollo 12 & Apollo 17 were more robust than those grown in samples taken during Apollo 11 . A. thaliana has been extensively studied as

4536-575: The production of proteins in various ways. The recruitment of Argonaute proteins to targeted mRNA can induce mRNA degradation. The Argonaute-miRNA complex can also affect the formation of functional ribosomes at the 5′-end of the mRNA. The complex here competes with the translation initiation factors and/or abrogate ribosome assembly. Also, the Argonaute-miRNA complex can adjust protein production by recruiting cellular factors such as peptides or post translational modifying enzymes, which degrade

4608-473: The retraction of the claim from the leading journal. In 2017, a group from University of Illinois reported using a prokaryotic Argonaute protein taken from Pyrococcus furiosus (PfAgo) along with guide DNA to edit DNA in vitro as artificial restriction enzymes . PfAgo based artificial restriction enzymes were also used for storing data on native DNA sequences via enzymatic nicking. Arabidopsis thaliana Arabis thaliana Arabidopsis thaliana ,

4680-683: The scientific literature are Ws, or Wassilewskija, C24, Cvi, or Cape Verde Islands, Nossen, etc. (see for ex. ) Sets of closely related accessions named Col-0, Col-1, etc., have been obtained and characterized; in general, mutant lines are available through stock centers, of which best-known are the Nottingham Arabidopsis Stock Center-NASC and the Arabidopsis Biological Resource Center-ABRC in Ohio, USA. The Col-0 accession

4752-474: The sequence conservation of PAZ and PIWI domains across the family, the uniqueness of AGO2 is presumed to arise from either the N-terminus or the spacing region linking PAZ and PIWI motifs. Several AGO family members in plants also attract study. AGO1 is involved in miRNA related RNA degradation, and plays a central role in morphogenesis. In some organisms, it is strictly required for epigenetic silencing. It

4824-529: The smallest genomes among plants. It was long thought to have the smallest genome of all flowering plants, but that title is now considered to belong to plants in the genus Genlisea , order Lamiales , with Genlisea tuberosa , a carnivorous plant, showing a genome size of approximately 61 Mbp. It was the first plant genome to be sequenced, completed in 2000 by the Arabidopsis Genome Initiative. The most up-to-date version of

4896-419: The suppression of the genes and proteins of class I KNOX family (such as SHOOT APICAL MERISTEMLESS ). These class I KNOX proteins directly suppress gibberellin biosynthesis in the leaf primordium. Many genetic factors were found to be involved in the suppression of these class I KNOX genes in leaf primordia (such as ASYMMETRIC LEAVES1, BLADE-ON-PETIOLE1 , SAWTOOTH1 , etc.). Thus, with this suppression,

4968-490: The then-current technologies, while maize was a well-established genetic model for plant biology. The breakthrough year for A. thaliana as a model plant was 1986, in which T-DNA -mediated transformation and the first cloned A. thaliana gene were described. Due to the small size of its genome , and because it is diploid , Arabidopsis thaliana is useful for genetic mapping and sequencing — with about 157 megabase pairs and five chromosomes , A. thaliana has one of

5040-456: Was selected by Rédei from within a (nonirradiated) population of seeds designated 'Landsberg' which he received from Laibach. Columbia (named for the location of Rédei's former institution, University of Missouri - Columbia ) was the reference accession sequenced in the Arabidopsis Genome Initiative. The Later (Landsberg erecta) line was selected by Rédei (because of its short stature) from a Landsberg population he had mutagenized with X-rays. As

5112-421: Was transformed into Nicotiana benthamiana , tobacco plant that does not recognize EF-Tu, thereby permitting recognition of bacterial EF-Tu thereby confirming EFR as the receptor of EF-Tu. Both FLS2 and EFR use similar signal transduction pathways to initiate PTI. A. thaliana has been instrumental in dissecting these pathways to better understand the regulation of immune responses, the most notable one being

5184-445: Was used to determine the genes responsible for nonhost resistance is Blumeria graminis , the causal agent of powdery mildew of grasses. A. thaliana mutants were developed using the mutagen ethyl methanesulfonate and screened to identify mutants with increased infection by B. graminis . The mutants with higher infection rates are referred to as PEN mutants due to the ability of B. graminis to penetrate A. thaliana to begin

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