Recombinant Cry1Ia protein is highly toxic to cotton boll weevil (Anthonomus grandis Boheman) and fall armyworm (Spodoptera frugiperda).
OBJECTIVE
To evaluate the activity of cry1Ia gene against cotton pests, Spodoptera frugiperda and Anthonomus grandis.


RESULTS
Had isolated and characterized a toxin gene from the Bacillus thuringiensis S1451 strain which have been previously shown to be toxic to S. frugiperda and A. grandis. The toxin gene (cry1Ia) was amplified by PCR, sequenced, and cloned into the genome of a baculovirus. The Cry1Ia protein was expressed in baculovirus infected insect cells, producing protein inclusions in infected cells. The Cry1Ia protein has used in bioassays against to S. frugiperda and A. grandis.


CONCLUSIONS
Bioassays using the purified recombinant protein showed high toxicity to S. frugiperda and A. grandis larvae. Molecular modelling of the Cry1Ia protein translated from the DNA sequence obtained in this work, showed that this protein possibly posses a similar structure to the Cry3A protein. Ultrastructural analysis of midgut cells from A. grandis incubated with the Cry1Ia toxin, showed loss of microvilli integrity.


CONCLUSIONS
The results indicate that the cry1Ia is a good candidate for the construction of transgenic plants resistant to these important cotton pests.
Martins
E S
ES
University of Brasília, Cell Biology, Campus Universitário, Asa Norte, Brasília, DF, Brasil.
Aguiar
R W D S
RW
Martins
N F
NF
Melatti
V M
VM
Falcão
R
R
Gomes
A C M M
AC
Ribeiro
B M
BM
Monnerat
R G
RG
D000818:Animals; D001413:Bacillus thuringiensis; D001426:Bacterial Proteins / Q000235:genetics / Q000633:toxicity*; D001427:Bacterial Toxins / Q000235:genetics / Q000633:toxicity*; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D001681:Biological Assay; D003001:Cloning, Molecular; D015870:Gene Expression; D003368:Gossypium / Q000382:microbiology; D007306:Insecticides / Q000633:toxicity*; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000648:ultrastructure; D007814:Larva / Q000821:virology; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000633:toxicity; D018411:Spodoptera / Q000187:drug effects* / Q000821:virology; D014162:Transfection / Q000379:methods; D048889:Weevils / Q000187:drug effects* / Q000821:virology
D001426:Bacterial Proteins; D001427:Bacterial Toxins; C406926:CRY1BD protein, Bacillus thuringiensis; D007306:Insecticides; D011994:Recombinant Proteins