Resumen

LAURA EVANGELINA GARCIA; SANCHEZ-PUERTA, M VIRGINIA

Mendoza

Simposio; Simposio de investigadores Jóvenes SAIB 2022; 2022

SAIB

“Low efficiency in the splicing of foreign mitochondrial genes in Lophophytum”Plant organelles arose from two independent endosymbiotic events. Along the evolution, thenucleus took control of the mitochondria and the chloroplast, regulating processes that occur inthem, including gene expression. Many mitochondrial genes have group II introns that have losttheir ability to auto splicing. Nuclear factors assist the maturation of organellar transcripts. Thisinteraction between genes encoded by two physically separate genomes requires close coordinationand is critical for mitochondrial functions. The functional consequences of the rupture in thecoordination between both genomes due to foreign genes remain unexplored. In the holoparasiticplant Lophophytum Mirabile, a large part of the genes encoded in the mitochondrial genome isforeign. This scenario challenges the close coordination between the nucleus and the organelles;nuclear factors involved in mitochondrial gene splicing must interact with unknown molecules. Tounderstand how Lophophytum resolves this apparent nucleo-cytoplasmic coordination breakdown,we measured the splicing efficiency of Lophophytum mitochondrial genes. The values obtainedwere compared with the SE from other angiosperms using RNAseq sequencing data. Furthermore,we investigated the origin of nuclear splicing factors. In general, the splicing efficiency inLophophytum is significantly lower than that of the other angiosperms analyzed. Phylogeneticanalysis revealed a native origin for the splicing factors in Lophophytum. These results reinforcethe hypothesis of the necessary coordination between both genomes and raise new questions aboutthe respiratory efficiency of Lophophytum and its consequences on evolution.