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Baulcombe, D. C.

Publications and source records attributed to Baulcombe, D. C..

2 recordsLinked to original sources

A first global phylogeny of Maize chlorotic mottle virus

Maize chlorotic mottle virus has been rapidly spreading around the globe over the past decade. The interactions of Maize chlorotic mottle virus with potyviridae viruses causes an aggressive synergistic viral condition - maize lethal necrosis, which can cause total yield loss. Maize production in sub-Saharan Africa, where it is the most important cereal, is threatened by the arrival of maize lethal necrosis. We obtained Maize chlorotic mottle virus genome sequences from across East Africa and for the first time from Ecuador and Hawaii, and constructed a phylogeny which highlights the similarity of Chinese to African isolates, and Ecuadorian to Hawaiian isolates. We used a measure of clustering, the adjusted Rand index, to extract region-specific SNPs and coding variation that can be used for diagnostics. The population genetics analysis we performed shows that the majority of sequence diversity is partitioned between populations, with diversity extremely low within China and East Africa.

plant biology

mRNA turnover through CDS-targeting is the primary role of miRNA in the green alga Chlamydomonas.

MicroRNAs regulate gene expression as part of the RNA-induced silencing complex, where the sequence identity of the miRNA provides the specificity to the target messenger RNA, and the result is target repression. The mode of repression can be through target cleavage, RNA destabilization and/or decreased translational efficiency. Here, we provide a comprehensive global analysis of the evolutionarily distant unicellular green alga Chlamydomonas reinhardtii to quantify the effects of miRNA on protein synthesis and RNA abundance. We show that, similar to metazoan systems, miRNAs in Chlamydomonas regulate gene-expression primarily by destabilizing mRNAs. However, unlike metazoan miRNA where target site utilization localizes mainly to 3UTRs, in Chlamydomonas utilized target sites lie predominantly within coding regions. These results demonstrate that destabilization of mRNA is the main evolutionarily conserved mode of action for miRNAs, but details of the mechanism diverge between plant and metazoan kingdoms.

molecular biology