0000000000894334
AUTHOR
R.a. De Maagd
Functional interactions between members of the REPAT family of insect pathogen-induced proteins
Studies on the transcriptional response to pathogens in the insect larval gut have shown the regulation of several genes after the infection. Repat (REsponse to PAThogens) genes were first identified in Spodoptera exigua midgut as being up-regulated in response to the exposure to Bacillus thuringiensis toxins and baculovirus. Recently, new members of the REPAT family showed a constitutive up-regulation in a B. thuringiensis-resistant population. Based on a yeast two-hybrid screening, we have detected the interaction of REPAT1 with other members of the REPAT family, leading to the discovery of a new member: REPAT8. The functional role of this interaction was shown by following the changes of…
Role of Bacillus thuringiensis Toxin Domains in Toxicity and Receptor Binding in the Diamondback Moth
ABSTRACT The toxic fragment of Bacillus thuringiensis crystal proteins consists of three distinct structural domains. There is evidence that domain I is involved in pore formation and that domain II is involved in receptor binding and specificity. It has been found that, in some cases, domain III is also important in determining specificity. Furthermore, involvement of domain III in binding has also been reported recently. To investigate the role of toxin domains in the diamondback moth ( Plutella xylostella ), we used hybrid toxins with domain III substitutions among Cry1C, Cry1E, and Cry1Ab. Neither Cry1E nor G27 (a hybrid with domains I and II from Cry1E and domain III from Cry1C) was to…