The resistance of cowpea seeds to bruchid beetles is not related to levels of cysteine proteinase inhibitors.
A cDNA encoding a cysteine proteinase inhibitor was isolated from a cDNA library prepared from developing seeds of an insect-resistant line of cowpea. The sequence of the encoded protein was homologous with those of other plant cysteine endoproteinase inhibitors, and with Type 2 cystatins from animals. Southern blot analyses indicated that small gene families were present in both resistant and susceptible lines of cowpea, while northern blot analyses showed similar levels of expression. It is concluded that the levels of expression of the inhibitor do not account for the differences in insect resistance of the two lines.
Fernandes
K V
KV
Department of Agricultural Sciences, University of Bristol, AFRC Institute of Arable Crops Research, UK.
Sabelli
P A
PA
Barratt
D H
DH
Richardson
M
M
Xavier-Filho
J
J
Shewry
P R
PR
D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D001517:Coleoptera / Q000276:immunology / Q000502:physiology*; D015853:Cysteine Proteinase Inhibitors / Q000235:genetics*; D008969:Molecular Sequence Data; D018521:Plant Physiological Phenomena; D010944:Plants / Q000235:genetics / Q000276:immunology; D017386:Sequence Homology, Amino Acid
D015853:Cysteine Proteinase Inhibitors