These authors contributed equally to this work.
The role of floral organs in carpels, an Arabidopsis loss-of-function mutation in MicroRNA160a, in organogenesis and the mechanism regulating its expression
Article first published online: 3 FEB 2010
© 2010 The Authors. Journal compilation © 2010 Blackwell Publishing Ltd
The Plant Journal
Volume 62, Issue 3, pages 416–428, May 2010
How to Cite
Liu, X., Huang, J., Wang, Y., Khanna, K., Xie, Z., Owen, H. A. and Zhao, D. (2010), The role of floral organs in carpels, an Arabidopsis loss-of-function mutation in MicroRNA160a, in organogenesis and the mechanism regulating its expression . The Plant Journal, 62: 416–428. doi: 10.1111/j.1365-313X.2010.04164.x
- Issue published online: 16 APR 2010
- Article first published online: 3 FEB 2010
- Received 28 September 2009; revised 14 January 2010; accepted 19 January 2010; published online 12 March 2010.
- AUXIN RESPONSE FACTOR;
MicroRNAs (miRNAs) have emerged as key regulators of gene expression at the post-transcriptional level in both plants and animals. However, the specific functions of MIRNAs (MIRs) and the mechanisms regulating their expression are not fully understood. Previous studies showed that miR160 negatively regulates three genes that encode AUXIN RESPONSE FACTORs (ARF10, -16, and -17). Here, we characterized floral organs in carpels (foc), an Arabidopsis mutant with a Ds transposon insertion in the 3′ regulatory region of MIR160a. foc plants exhibit a variety of intriguing phenotypes, including serrated rosette leaves, irregular flowers, floral organs inside siliques, reduced fertility, aberrant seeds, and viviparous seedlings. Detailed phenotypic analysis showed that abnormal cell divisions in the basal embryo domain and suspensor led to diverse defects during embryogenesis in foc plants. Further analysis showed that the 3′ region was required for the expression of MIR160a. The accumulation of mature miR160 was greatly reduced in foc inflorescences. In addition, the expression pattern of ARF16 and -17 was altered during embryo development in foc plants. foc plants were also deficient in auxin responses. Moreover, auxin was involved in regulating the expression of MIR160a through its 3′ regulatory region. Our study not only provides insight into the molecular mechanism of embryo development via MIR160a-regulated ARFs, but also reveals the mechanism regulating MIR160a expression.