CAS scientists make new advances about the nuclear speckle research of plant cells

Serine/arginine-rich (SR) proteins are evolutionarily conserved proteins in animals and plants, which play important roles in spliceosome assembly and splicing. Plants have a much higher number of SR proteins than animals. However, little is known regarding the biological functions of SR proteins in plants due to their functional redundancy.

Using genetic analyses, Dr. FANG Yuda and his colleagues at Shanghai Institute of Plant Physiology and Ecology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, find that loss of the functions of SC35 and SC35-like (SCL), which are the classic SR proteins in the modle plant Arabidopsis, cause pleiotropic changes in plant morphology and development, including serrated leaves, late flowering, shorter roots and abnormal silique phyllotaxy. SC35/SCL proteins localize in nuclear speckles and interact with U1/U2 snRNPs (U1-70K and U2AF65a). SC35/SCL protein affects the transcription and splicing of a subset of Arabidopsis genes largely through binding to a specific RNA sequence containing the AGAAGA motif. For example, Dr. Fang and his colleagues reveal that the late flowering time phenotype of sc35-scl quintuple mutant is due to elevated level of a flowering time repressor gene named FLOWERING LOCUS C (FLC). In the absense of SC35/SCL, the transcription and pre-mRNA splicing of FLC is enhanced. Together, these findings provide a mechanistic insight into the functions of SC35 and SCL proteins in the regulation of splicing and transcription to maintain the proper expression of genes and development in plants.

The work entitled “Depletion of Arabidopsis SC35 and SC35-like serine/arginine-rich proteins affects the transcription and splicing of a subset of genes” has been published online in the “PLoS Genetics” on 8th Mar. 2017.

This research is financially supported by National Natural Science Foundation of China.


Author contact:
FANG Yuda, Ph.D., National key Laboratory of Plant Molecular Genetic, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032 Tel: +86-21-54924296, Fax: +86-21-54924015, Email: yfang@sibs.ac.cn