Translational polymorphism as a potential source of plant proteins variety in Arabidopsis thaliana.
BACKGROUND
According to scanning model, 40S ribosomal subunits can either initiate translation at start AUG codon in suboptimal context or miss it and initiate translation at downstream AUG(s), thereby producing several proteins. Functional significance of such a protein translational polymorphism is still unknown.


RESULTS
We compared predicted subcellular localizations of annotated Arabidopsis thaliana proteins and their potential N-terminally truncated forms started from the nearest downstream in-frame AUG codons. It was found that localizations of full and N-truncated proteins differ in many cases: 12.2% of N-truncated proteins acquired sorting signals de novo and 5.7% changed their predicted subcellular locations (mitochodria, chloroplast or secretory pathway). It is likely that the in-frame downstream AUGs may be frequently utilized to synthesize proteins possessing new functional properties and such a translational polymorphism may serve as an important source of cellular and organelle proteomes.
Institute of Cytology and Genetics, Pr. Lavrentieva 10, Novosibirsk 630090, Russia. Alex.Kochetov@bionet.nsc.ru
Alex V
AV
Kochetov
Akinori
A
Sarai
D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D022082:Cellular Structures / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods*; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D005787:Gene Frequency; D014644:Genetic Variation; D011110:Polymorphism, Genetic; D014176:Protein Biosynthesis / Q000235:genetics*; D020543:Proteome / Q000235:genetics* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020539:Sequence Analysis, Protein
D029681:Arabidopsis Proteins; D020543:Proteome; D012333:RNA, Messenger