Expansin

Expansins are a family of closely related nonenzymatic proteins found in the plant cell wall, with important roles in plant cell growth, fruit softening, abscission, emergence of root hairs, pollen tube invasion of the stigma and style, meristem function, and other developmental processes where cell wall loosening occurs.[1] Expansins were originally discovered as mediators of acid growth, which refers to the widespread characteristic of growing plant cell walls to expand faster at low (acidic) pH than at neutral pH.[2] Expansins are thus linked to auxin action. They are also linked to cell enlargement and cell wall changes induced by other plant hormones such as gibberellin,[3] cytokinin,[4] ethylene[5] and brassinosteroids.[6]

A subset of the β-expansins are also the major group-1 allergens of grass pollens.[7]

  1. ^ Cosgrove DJ (September 2000). "Loosening of plant cell walls by expansins" (PDF). Nature. 407 (6802): 321–6. Bibcode:2000Natur.407..321C. doi:10.1038/35030000. PMID 11014181. S2CID 4358466. Archived from the original (PDF) on 2006-09-08. Retrieved 2009-01-09.
  2. ^ McQueen-Mason S, Durachko DM, Cosgrove DJ (November 1992). "Two endogenous proteins that induce cell wall extension in plants". Plant Cell. 4 (11): 1425–33. doi:10.1105/tpc.4.11.1425. JSTOR 3869513. PMC 160229. PMID 11538167.
  3. ^ Cho HT, Kende H (September 1997). "Expression of expansin genes is correlated with growth in deepwater rice". Plant Cell. 9 (9): 1661–71. doi:10.1105/tpc.9.9.1661. PMC 157041. PMID 9338967.
  4. ^ Downes BP, Crowell DN (June 1998). "Cytokinin regulates the expression of a soybean β-expansin gene by a post-transcriptional mechanism" (PDF). Plant Mol. Biol. 37 (3): 437–44. doi:10.1023/A:1005920732211. PMID 9617811. S2CID 1815686.
  5. ^ Cho HT, Cosgrove DJ (December 2002). "Regulation of root hair initiation and expansin gene expression in Arabidopsis". Plant Cell. 14 (12): 3237–53. doi:10.1105/tpc.006437. PMC 151215. PMID 12468740.
  6. ^ Sun Y, Veerabomma S, Abdel-Mageed HA, et al. (August 2005). "Brassinosteroid regulates fiber development on cultured cotton ovules". Plant Cell Physiol. 46 (8): 1384–91. doi:10.1093/pcp/pci150. PMID 15958497.
  7. ^ Cosgrove DJ, Bedinger P, Durachko DM (June 1997). "Group I allergens of grass pollen as cell wall-loosening agents". Proc. Natl. Acad. Sci. U.S.A. 94 (12): 6559–64. Bibcode:1997PNAS...94.6559C. doi:10.1073/pnas.94.12.6559. PMC 21089. PMID 9177257.