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Arabidopsis proline-rich protein important for development and abiotic stress tolerance is involved in microRNA biogenesis.

ABSTRACT: MicroRNAs (miRNAs) are important for plant development and stress responses. However, factors regulating miRNA metabolism are not completely understood. SICKLE (SIC), a proline-rich protein critical for development and abiotic stress tolerance of Arabidopsis, was identified in this study. Loss-of-function sic-1 mutant plants exhibited a serrated, sickle-like leaf margin, reduced height, delayed flowering, and abnormal inflorescence phyllotaxy, which are common characteristics of mutants involved in miRNA biogenesis. The sic-1 mutant plants accumulated lower levels of a subset of miRNAs and transacting siRNAs but higher levels of corresponding primary miRNAs than the WT. The SIC protein colocalizes with the miRNA biogenesis component HYL1 in distinct subnuclear bodies. sic-1 mutant plants also accumulated higher levels of introns from hundreds of loci. In addition, sic-1 mutant plants are hypersensitive to chilling and salt stresses. These results suggest that SIC is a unique factor required for the biogenesis of some miRNAs and degradation of some spliced introns and important for plant development and abiotic stress responses.

SUBMITTER: Zhan X

PROVIDER: S-EPMC3497810 | biostudies-other | 2012 Oct

REPOSITORIES: biostudies-other

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Arabidopsis proline-rich protein important for development and abiotic stress tolerance is involved in microRNA biogenesis.

Zhan Xiangqiang X Wang Bangshing B Li Hongjiang H Liu Renyi R Kalia Rajwant K RK Zhu Jian-Kang JK Chinnusamy Viswanathan V

Proceedings of the National Academy of Sciences of the United States of America 20121015 44

MicroRNAs (miRNAs) are important for plant development and stress responses. However, factors regulating miRNA metabolism are not completely understood. SICKLE (SIC), a proline-rich protein critical for development and abiotic stress tolerance of Arabidopsis, was identified in this study. Loss-of-function sic-1 mutant plants exhibited a serrated, sickle-like leaf margin, reduced height, delayed flowering, and abnormal inflorescence phyllotaxy, which are common characteristics of mutants involved ...[more]

PMID: 23071326

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Arabidopsis proline-rich protein important for development and abiotic stress tolerance is involved in microRNA biogenesis.

Publications

Arabidopsis proline-rich protein important for development and abiotic stress tolerance is involved in microRNA biogenesis.

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