The Brachypodium pangenomereveals differently evolved drought responsive dehydrin genes within its species.

GALVEZ ROJAS S.; AGOSTINI F.

Sevilla España

Congreso; VII BIENNIAL CONGRESS OF SESBE; 2020

Sociedad Española de Biología Evolutiva

Dehydrins (DHNs) belong to group 2 LEA (Late-Embryogenesis-Abundant) proteins which play an important role in plant responses to abiotic stresses. DHN data wasretrieved from Phytozome and Ensembl Plants and used to perform comparative evolutionary analysis of dehydrin genes in four Brachypodiumspecies, 54 B. distachyon ecotypes and five cereal crops (Aegilops tauschii, Hordeum vulgare, Sorghum bicolor, Oryza sativaand Zea mays). DHN domain analysis across the four Brachypodiumspecies dehydrins (Bdhn) revealed eight architectures. The most common architecture was YSK2. In addition, some upstream cis-elements related to exogenous and endogenous stresses were detected. B. distachyon (Bdis) drought-tolerant ecotypes contain a slightly lower number of dehydrins (4 vs. 9), and some of them have a distinct sequence composition. Chromosome distribution of Bdhn genes differ among Bdis ecotypes as well as the number of DHNs in each chromosome. Seven out of nine Bdhn genes are located in Bdis chromosomes 3 and 4 and one gene each in chromosomes 1 and 2. Phylogenetic analysis of DHN sequences show a general evolutionary trend of early diverging B. stacei and its derived (sister) B. hybridum?S subgenome Bdhns, followed by those of B. distachyon and sister B. hybridum?D subgenome Bdhns, and those of B. sylvaticum. However B. sylvaticum, a moist-environment perennial species, contains nine DHNs, four of which diverge from any of the nine DHNs present in the annual dry-environment Brachypodiumspecies. Further analysis of orthologous sequences shows that only Bdhn1 and 2 are present in every grass studied