Evolutionary analysis of the SUB1 locus across the Oryza genomes.
BACKGROUND
Tolerance to complete submergence is recognized in a limited number of Asian rice (Oryza sativa L.) varieties, most of which contain submergence-inducible SUB1A on the polygenic SUBMERGENCE-1 (SUB1) locus. It has been shown that the SUB1 locus encodes two Ethylene-Responsive Factor (ERF) genes, SUB1B and SUB1C, in all O. sativa varieties. These genes were also found in O rufipogon and O nivara, wild relatives of O. sativa. However, detailed analysis of the polygenic locus in other Oryza species has not yet been made.


RESULTS
Chromosomal location, phylogenetic, and gene structure analyses have revealed that the SUB1 locus is conserved in the long arm of chromosome 9 in most Oryza species. We also show that the SUB1A-like gene of O. nivara is on chromosome 1 and that Leersia perrieri, a grass-tolerant to deep-flooding, presents three ERF genes in the SUB1 locus.


CONCLUSIONS
We provide here a deeper insight into the evolutionary origin and variation of the SUB1 locus and raise the possibility that an association of these genes with flooding tolerance in L. perrieri may exist.
Technology Development Center (CDTec), Universidade Federal de Pelotas, Pelotas, Brazil.|Plant Genomics and Breeding Center (CGF), Universidade Federal de Pelotas, Pelotas, Brazil.
Railson Schreinert
RS
Dos Santos
Plant Genomics and Breeding Center (CGF), Universidade Federal de Pelotas, Pelotas, Brazil.
Daniel da Rosa
DDR
Farias
Plant Genomics and Breeding Center (CGF), Universidade Federal de Pelotas, Pelotas, Brazil.
Camila
C
Pegoraro
Technology Development Center (CDTec), Universidade Federal de Pelotas, Pelotas, Brazil.
Cesar Valmor
CV
Rombaldi
Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg, USA.
Takeshi
T
Fukao
The School of Plant Sciences, Ecology & Evolutionary Biology, Arizona Genomics Institute, Tucson, USA.
Rod A
RA
Wing
Technology Development Center (CDTec), Universidade Federal de Pelotas, Pelotas, Brazil. acostol@cgfufpel.org.|Plant Genomics and Breeding Center (CGF), Universidade Federal de Pelotas, Pelotas, Brazil. acostol@cgfufpel.org.
Antonio Costa
AC
de Oliveira
IOMAP; Leersia perrieri; Oryza; SUB1 genes; Submergence tolerance