Callose
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Callose is a plant polysaccharide. Its production is due to the glucan synthase-like gene (GLS) in various places within a plant. It is produced to act as a temporary cell wall in response to stimuli such as stress or damage.cite-ref-1[1] Callose is composed of glucose residues linked together through β-1,3-linkages, and is termed a β-glucan. It is thought to be manufactured at the cell wall by callose synthases and is degraded by β-1,3-glucanases. Callose is very important for the permeability of plasmodesmata (Pd) in plants; the plant's permeability is regulated by plasmodesmata callose (PDC). PDC is made by callose synthases and broken down by β-1,3-glucanases (BGs). The amount of callose that is built up at the plasmodesmatal neck, which is brought about by the interference of callose synthases (CalSs) and β-1,3-glucanases, determines the conductivity of the plasmodesmata.cite-ref-2[2]
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• See also
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Formation and function
Callose is laid down at plasmodesmata, at the cell plate during cytokinesis, and during pollen development. Endothecium contains a substance callose, which makes it thicker. Callose is produced in response to wounding, infection by pathogens,cite-ref-vcrb2012b2-3-0[3] aluminium, and abscisic acid. When there is wounding in the plant tissue, it is fixed by the deposition of callose at the plasmodesmata and cell wall; this process happens within minutes after damage. Even though callose is not a constitutional component of the plant's cell wall, it is related to the plant's defense mechanism.cite-ref-4[4] Deposits often appear on the sieve plates at the end of the growing season.cite-ref-5[5] Callose also forms immediately around the developing meiocytes and tetrads of sexually reproducing angiosperms but is not found in related apomictic taxa.cite-ref-6[6] Callose deposition at the cell wall has been suggested as an early marker for direct somatic embryogenesis from cortical and epidermal cells of Cichorium hybrids.cite-ref-7[7] Temporary callose walls are also thought to be a barrier between a cell and its environment, while the cell is undergoing a genetic programming that allows it to differentiate.cite-ref-8[8] This is because callose walls can be found around nucellar embryos during Nucellar embryony.cite-ref-9[9]
See also
References
cite-note-vcrb2012b2-33. ↑ citerefnowickilichockanowakowskak-osi-ska2012Nowicki M, Lichocka M, Nowakowska M, Kłosińska U, Kozik EU (January 2012). "A Simple Dual Stain for Detailed Investigations of Plant-Fungal Pathogen Interactions". Vegetable Crops Research Bulletin. 77 (1): 61–74. doi:10.2478/v10032-012-0016-z.
cite-note-66. ↑ citerefcarmancraneriera-lizarazu1991Carman JG, Crane CF, Riera-Lizarazu O (1991). "Comparative Histology of Cell Walls during Meiotic and Apomeiotic Megasporogenesis in Two Hexaploid Australasian Elymus Species". Crop Science. 31 (6): 1527. doi:10.2135/cropsci1991.0011183X003100060029x.
cite-note-88. ↑ citereftuckerpaechwillemsekoltunow2001Tucker MR, Paech NA, Willemse MT, Koltunow AM (2001). "Dynamics of callose deposition and β-1,3-glucanase expression during reproductive events in sexual and apomictic Hieracium". Planta. 212 (4): 487–498. doi:10.1007/s004250000445. PMID 11525505. S2CID 12073031.