Biotech Updates

OsSLA4 Plays a Role in Chloroplast Development in Rice

June 13, 2018

In land plants, chloroplast transcripts undergo post-transcriptional modifications, including splicing, editing, trimming, before translation. This essential step is regulated by a set of nuclear-encoded proteins. Zhong-wei Wang from the China National Rice Research Institute characterized a rice (Oryza sativa) seedling-lethal albino mutant, sla4.

The sla4 mutant exhibited an albino phenotype from germination through the third-leaf stage, and then gradually died. The sla4 mutants also lacked photosynthetic pigments and had severe defects in photosynthesis and early chloroplast development. Analysis showed that a 13-base pair deletion in the coding region of OsSLA4 on chromosome 7 resulted in the albino phenotype. The albino mutants were also generated by knocking-out OsSLA4 using the CRISPR-Cas9 system. OsSLA4 was found to encode a chloroplast-localized pentatricopeptide repeat (PPR) protein.

Loss-of-function of OsSLA4 resulted in severe defects in the intron splicing of several genes as well as a significant reduction in the transcript levels of chloroplast ribosomal RNAs and some chloroplast development- and photosynthesis-related genes.

These results indicate that OsSLA4 is important for early chloroplast development and seedling growth in rice.

For more information, read the article in Plant Growth Regulation.