Pisum sativum contains a factor with strong homology to eIF5B.
Immunoscreening of a cDNA expression library, prepared from 7 days old young shoots of pea (Pisum sativum), identified a novel gene comprising of 2586 bp open reading frame (ORF) with 381 bp and 532 bp 5' and 3'untranslated regions (UTRs), respectively. Sequence analysis of this gene, termed as PeIF5B, revealed striking homology to eukaryotic translation initiation factor eIF5B - a sequence homologue of prokaryotic translation initiation factor IF2. Southern blot analyses indicated that PeIF5B exists as a single copy gene in P. sativum genome. Northern blot hybridization revealed the presence of a 7 kb transcript in pea plant. In vitro translation using rabbit reticulocyte lysate system yielded a protein corresponding to 116 kDa which was higher than the calculated value of 96 kDa. Phylogenetic analyses of PeIF5B placed it closer to eIF5B from yeast, human and Drosophila. Pfam domain search analysis pointed to its likely role as a translation initiation factor. The presence of an eIF5B-like factor in a plant system will aid in better understanding of the mechanism of translation initiation in plants.
Rasheedi
Sheeba
S
Laboratory of Molecular and Cellular Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500 076, India.
Ghosh
Sudip
S
Suragani
Madhuri
M
Tuteja
Narendra
N
Sopory
Sudhir K
SK
Hasnain
Seyed E
SE
Ehtesham
Nasreen Z
NZ
D020413:3' Untranslated Regions; D000595:Amino Acid Sequence; D000818:Animals; D029968:Escherichia coli Proteins / Q000235:genetics; D039642:Eukaryotic Initiation Factors / Q000235:genetics*; D015723:Gene Library; D006801:Humans; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000235:genetics*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics*; D039881:Prokaryotic Initiation Factor-2 / Q000235:genetics; D011817:Rabbits; D017386:Sequence Homology, Amino Acid
D020413:3' Untranslated Regions; D029968:Escherichia coli Proteins; D039642:Eukaryotic Initiation Factors; D010940:Plant Proteins; D039881:Prokaryotic Initiation Factor-2; C451459:eukaryotic initiation factor-5B