Cloning and structural analysis of an Indian little millet (Panicum sumatrense) zein-like storage protein: implications for molecular assembly.
Zeins are prolamin storage proteins that accumulate in kernel endosperm of several cereals. For cloning of genes coding for zein-like proteins that accumulate in enhanced quantities in the filling stages of little millet (Panicum sumatrense Roth.) developing grains, RT-PCR was performed using specific primers. A 750-bp cDNA was directly sequenced and in silico analysis showed high identity degree to alpha-prolamins. This family is composed of zeins from Zea mays, coixins from Coix lachryma-jobi, and alpha-kafirins from Sorghum bicolor. The putative conserved domain of zein-like proteins was identified by primary structure comparisons. Furthermore, threading analyses indicated that the millet zein-like protein forms an anti-parallel alpha-helical hairpin with two opposite surfaces: one hydrophobic and the other hydrophilic that probably could be involved in protein storage assembly. Knowledge about zein-like alpha-prolamins in little millet will lead to cloning and transfer of this gene to other major food crops, such as cereals and legumes, with inferior nutritional quality for monogastric animals.
Sivakumar
S
S
Center for Plant Molecular Biology, Tamil Nadu Agricultural University, Coimbatore-641 003, India. subarayansivakumar@yahoo.com
Franco
O L
OL
Thayumanavan
B
B
Murad
A M
AM
Manickam
A
A
Mohan
M
M
Mridula
M
M
D000595:Amino Acid Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D017124:Conserved Sequence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D005810:Multigene Family; D008897:Panicum / Q000235:genetics*; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D015028:Zein / Q000737:chemistry* / Q000235:genetics*
D015028:Zein