miR172 microRNA precursor family
| miR172 microRNA precursor family | |
|---|---|
Predicted secondary structure and sequence conservation of miR172 | |
| Identifiers | |
| Symbol | miR172 |
| Rfam | RF00452 |
| miRBase | MI0000215 |
| miRBase family | MIPF0000035 |
| Other data | |
| RNA type | microRNA |
| Domain | Viridiplantae |
| GO | GO:0035195 GO:0035068 |
| SO | SO:0001244 |
| PDB structures | PDBe |
miR172 is a conserved plant microRNA that regulates developmental timing and reproductive development by targeting transcripts encoding APETALA2-like transcription factors. Members of the miR172 family are widely conserved across flowering plants and act as key regulators of flowering time, phase transitions, and floral organ identity.[1]
Function
miR172 regulates plant development primarily by repressing members of the APETALA2 (AP2) family of transcription factors. In Arabidopsis thaliana, miR172 can bind with high complementarity to the messenger RNA of APETALA2 and inhibit its expression mainly through translational repression.[2]
Overexpression of miR172 results in early flowering and defects in floral organ identity, consistent with reduced activity of AP2-like transcription factors that normally act as repressors of floral transition.[1]
Developmental phase transitions
miR172 plays a central role in developmental phase transitions in plants. In maize, accumulation of miR172 increases during shoot development and promotes the transition from juvenile to adult growth phases by downregulating the AP2-like gene glossy15.[3]
In Arabidopsis and related species, miR172 functions in a regulatory network with another conserved plant microRNA, miR156. miR156 levels are high during early development and decline with plant age, allowing increased expression of SPL transcription factors that promote the accumulation of miR172. This sequential regulatory cascade coordinates age-dependent flowering responses and developmental timing.[4][5]
Roles in reproductive development
Beyond flowering time control, miR172 also contributes to reproductive development and floral patterning. In maize, the microRNA encoded by the tasselseed4 locus regulates sex determination and meristem cell fate by targeting AP2-like genes involved in spikelet development.[6]
miR172 activity also influences fruit development. In Arabidopsis, regulatory interactions involving miR172 integrate developmental and hormonal signaling pathways to promote fruit growth.[7]
Evolution and conservation
The miR172 family is conserved across flowering plants and regulates diverse developmental processes through control of AP2-like transcription factors. Variation in the expression and regulatory interactions of miR172 contributes to differences in developmental timing and reproductive strategies among plant species.[1]
See also
References
- ^ a b c Aukerman MJ, Sakai H (2003). "Regulation of flowering time and floral organ identity by a microRNA and its APETALA2-like target genes". The Plant Cell. 15 (11): 2730–2741. doi:10.1105/tpc.016238. PMC 280575. PMID 14555699.
- ^ Chen X (2004). "A microRNA as a translational repressor of APETALA2 in Arabidopsis flower development". Science. 303 (5666): 2022–2025. doi:10.1126/science.1088060. PMC 5127708. PMID 12893888.
- ^ Lauter N, Kampani A, Carlson S, Goebel M, Moose SP (2005). "microRNA172 down-regulates glossy15 to promote vegetative phase change in maize". Proceedings of the National Academy of Sciences of the United States of America. 102 (26): 9412–9417. doi:10.1073/pnas.0503927102. PMC 1166634. PMID 15958531.
- ^ Bergonzi S, Albani MC, Ver Loren van Themaat E, Nordström KJ, Wang R, Schneeberger K, Moerland PD, Coupland G (2013). "Mechanisms of age-dependent response to winter temperature in perennial flowering of Arabis alpina". Science. 340 (6136): 1094–1097. doi:10.1126/science.1234116. PMID 23723236.
- ^ Zhou CM, Zhang TQ, Wang X, Yu S, Lian H, Tang H, Feng ZY, Zozomova-Lihová J, Wang JW (2013). "Molecular basis of age-dependent vernalization in Cardamine flexuosa". Science. 340 (6136): 1097–1100. doi:10.1126/science.1234340. PMID 23723237.
- ^ Chuck G, Meeley R, Irish E, Sakai H, Hake S (2007). "The maize tasselseed4 microRNA controls sex determination and meristem cell fate by targeting Tasselseed6/indeterminate spikelet1". Nature Genetics. 39 (12): 1517–1521. doi:10.1038/ng.2007.20. PMID 18026103.
- ^ Ripoll JJ, Bailey LJ, Mai QA, Wu SL, Hon CT, Chapman EJ, Ditta GS, Estelle M, Yanofsky MF (2015). "microRNA regulation of fruit growth". Nature Plants. 1 (4): 15036. doi:10.1038/nplants.2015.36. PMID 27247036.
External links