Vegetative phase change

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Vegetative phase change is the juvenile-to-adult transition in plants. [1] This transition is distinct from the reproductive transition and is most prolonged and pronounced in woody species. Manipulating phase change may be an important avenue for plant improvement. [2]

In the model plant Arabidopsis thaliana, vegetative phase change is relatively subtle: leaves become more curled, with an increased number of abaxial trichomes, and increased serration. [3] Studies in A. thaliana and maize identified microRNA MIR156 genes as master regulators of phase change, through their regulation of SQUAMOSA-PROMOTER-BINDING-LIKE (SBP/SPL) transcription factors. [4] [5] This gene regulatory circuit appears to be conserved (with variations) in all land plants, including mosses. [1]

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References

  1. 1 2 Poethig, R. S. (2010). "The past, present, and future of vegetative phase change". Plant Physiology. 154 (2): 541–544. doi:10.1104/pp.110.161620. PMC   2949024 . PMID   20921181.
  2. Chuck, G. S.; Tobias, C.; Sun, L.; Kraemer, F.; Li, C.; Dibble, D.; Arora, R.; Bragg, J. N.; Vogel, J. P.; Singh, S.; Simmons, B. A.; Pauly, M.; Hake, S. (2011). "Overexpression of the maize Corngrass1 microRNA prevents flowering, improves digestibility, and increases starch content of switchgrass". Proceedings of the National Academy of Sciences. 108 (42): 17550–17555. doi: 10.1073/pnas.1113971108 . PMC   3198312 . PMID   21987797.
  3. Telfer, A.; Bollman, K. M.; Poethig, R. S. (1997). "Phase change and the regulation of trichome distribution in Arabidopsis thaliana". Development. 124 (3): 645–654. doi:10.1242/dev.124.3.645. PMID   9043079.
  4. Wu, G.; Poethig, R. S. (2006). "Temporal regulation of shoot development in Arabidopsis thaliana by miR156 and its target SPL3". Development. 133 (18): 3539–3547. doi:10.1242/dev.02521. PMC   1610107 . PMID   16914499.
  5. Chuck, G.; Cigan, A. M.; Saeteurn, K.; Hake, S. (2007). "The heterochronic maize mutant Corngrass1 results from overexpression of a tandem microRNA". Nature Genetics. 39 (4): 544–549. doi:10.1038/ng2001. PMID   17369828. S2CID   20014922.