The chloroplast RNA splicing and ribosome maturation (CRM) domain is a RNA‐binding domain found in a plant‐specific protein family whose characterized members play essential roles in splicing group I and group II introns in mitochondria and chloroplasts. Together, these proteins are required for splicing of the majority of the approximately 20 chloroplast introns in land plants. Here, we provide evidence from
This content will become publicly available on January 30, 2025
Over the last 2 decades, routine collections in the Hawaiian Archipelago have expanded to mesophotic reefs, leading to the discovery of a new red algal genus and species, here described as
- PAR ID:
- 10502652
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Phycology
- Volume:
- 60
- Issue:
- 1
- ISSN:
- 0022-3646
- Format(s):
- Medium: X Size: p. 116-132
- Size(s):
- p. 116-132
- Sponsoring Org:
- National Science Foundation
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SUMMARY Setaria viridis and maize that an uncharacterized member of this family, CRM Family Member1 (CFM1), promotes the splicing of most of the introns that had not previously been shown to require a CRM domain protein. ASetaria mutant expressing mutated CFM1 was strongly disrupted in the splicing of three chloroplast tRNAs:trnI ,trnV andtrnA . Analyses by RNA gel blot and polysome association suggest that the tRNA deficiencies lead to compromised chloroplast protein synthesis and the observed whole‐plant chlorotic phenotypes. Co‐immunoprecipitation data demonstrate that the maize CFM1 ortholog is bound to introns whose splicing is disrupted in thecfm1 mutant. With these results, CRM domain proteins have been shown to promote the splicing of all but two of the introns found in angiosperm chloroplast genomes. -
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