Premium
A plant defensive cystatin (soyacystatin) targets cathepsin L‐like digestive cysteine proteinases (DvCALs) in the larval midgut of western corn rootworm ( Diabrotica virgifera virgifera )
Author(s) -
Koiwa Hisashi,
Shade Richard E.,
Zhu-Salzman Keyan,
D'Urzo Matilde Paino,
Murdock Larry L.,
Bressan Ray A.,
Hasegawa Paul M.
Publication year - 2000
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(00)01368-5
Subject(s) - western corn rootworm , cystatin , cathepsin l , biochemistry , proteolysis , biology , cysteine , cathepsin , proteinase inhibitor , cysteine proteinase inhibitors , enzyme , botany , larva , cystatin c , apoptosis , programmed cell death , renal function , caspase
Feeding bioassay results established that the soybean cysteine proteinase inhibitor N (soyacystatin N, scN) substantially inhibits growth and development of western corn rootworm (WCR), by attenuating digestive proteolysis [Zhao, Y. et al. (1996) Plant Physiol. 111, 1299–1306]. Recombinant scN was more inhibitory than the potent and broad specificity cysteine proteinase inhibitor E‐64. WCR digestive proteolytic activity was separated by mildly denaturing SDS–PAGE into two fractions and in‐gel assays confirmed that the proteinase activities of each were largely scN‐sensitive. Since binding affinity to the target proteinase [Koiwa, H. et al. (1998) Plant J. 14, 371–380] governs the effectiveness of scN as a proteinase inhibitor and an insecticide, five peptides (28–33 kDa) were isolated from WCR gut extracts by scN affinity chromatographic separation. Analysis of the N‐terminal sequence of these peptides revealed similarity to a cathepsin L‐like cysteine proteinase (DvCAL1, Diabrotica virgifera virgifera cathepsin L) encoded by a WCR cDNA. Our results indicate that cathepsin L orthologs are pivotal digestive proteinases of WCR larvae, and are targets of plant defensive cystatins (phytocystatins), like scN.