Differential gene expression in whitefly (Bemisia tabaci) B-biotype females and males under heat-shock condition

Bemisia tabaci (Insecta, Hemiptera, Aleyrodidae) females are more heat resistant than males, which has important ecological significance in adaptation and expansion of B. tabaci populations. Differentially expressed genes between 25 degrees C and 44 degrees C were identified by Suppression Subtractive Hybridization (SSH) in B. tabaci sexes. 50 and 83 differentially expressed Expression Sequence Tags (ESTs) were obtained from female and male libraries, respectively. The ESTs have four functional categories. The frequency of heat stress-related ESTs, metabolism-related ESTs and new ESTs was higher in males than females. However, the percentage of ESTs with unclassified functions was higher in females than males. Furthermore, three differentially expressed genes were further examined by real-time PCR. The results suggested that difference of heat-resistance under heat-shock condition was associated with differentially expressed genes in B. tabaci sexes, which might enable us to better understand the mechanism behind this ecologically important trait.