New insights on the evolution of Leafy cotyledon1 (LEC1) type genes in vascular plants.
NF-Y is a conserved oligomeric transcription factor found in all eukaryotes. In plants, this regulator evolved with a broad diversification of the genes coding for its three subunits (NF-YA, NF-YB and NF-YC). The NF-YB members can be divided into Leafy Cotyledon1 (LEC1) and non-LEC1 types. Here we presented a comparative genomic study using phylogenetic analyses to validate an evolutionary model for the origin of LEC-type genes in plants and their emergence from non-LEC1-type genes. We identified LEC1-type members in all vascular plant genomes, but not in amoebozoa, algae, fungi, metazoa and non-vascular plant representatives, which present exclusively non-LEC1-type genes as constituents of their NF-YB subunits. The non-synonymous to synonymous nucleotide substitution rates (Ka/Ks) between LEC1 and non-LEC1-type genes indicate the presence of positive selection acting on LEC1-type members to the fixation of LEC1-specific amino acid residues. The phylogenetic analyses demonstrated that plant LEC1-type genes are evolutionary divergent from the non-LEC1-type genes of plants, fungi, amoebozoa, algae and animals. Our results point to a scenario in which LEC1-type genes have originated in vascular plants after gene expansion in plants. We suggest that processes of neofunctionalization and/or subfunctionalization were responsible for the emergence of a versatile role for LEC1-type genes in vascular plants, especially in seed plants. LEC1-type genes besides being phylogenetic divergent also present different expression profile when compared with non-LEC1-type genes. Altogether, our data provide new insights about the LEC1 and non-LEC1 evolutionary relationship during the vascular plant evolution.
Programa de Pós-Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Brazil; Universidade Estadual do Rio Grande do Sul, Santa Cruz do Sul, Brazil.
Alexandro
A
Cagliari
Programa de Pós-Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Brazil; Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Brazil.
Andreia Carina
AC
Turchetto-Zolet
Programa de Pós-Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Brazil.
Ana Paula
AP
Korbes
Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Brazil.
Felipe Dos Santos
Fdos S
Maraschin
Programa de Pós-Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Brazil; Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Brazil; Departamento de Biofísica, Universidade Federal do Rio Grande do Sul, Brazil.
Rogerio
R
Margis
Programa de Pós-Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Brazil; Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Brazil. Electronic address: marcia.margis@ufrgs.br.
Marcia
M
Margis-Pinheiro
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics*; D001499:Bayes Theorem; D022762:CCAAT-Enhancer-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D016384:Consensus Sequence; D019143:Evolution, Molecular; D017343:Genes, Plant; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D010944:Plants / Q000235:genetics*
D029681:Arabidopsis Proteins; D022762:CCAAT-Enhancer-Binding Proteins; C113191:LEC1 protein, Arabidopsis
LEC1; LEC1-Like (L1L); Leafy cotyledon1 (LEC1)-type genes evolution; Seed maturation; Transcription factor