Galeruca daurica (Joannis) is a new outbreak pest in the Inner Mongolia grasslands in northern China. Heat shock protein 10 and 60 (Hsp10 and Hsp60) genes of G. daurica, designated as GdHsp10 and GdHsp60, were cloned by rapid amplification of cDNA ends techniques. Sequence analysis showed that GdHsp10 and GdHsp60 encoded polypeptides of 104 and 573 amino acids, respectively. Sequence alignment and phylogenetic analysis clearly revealed that the amino acids of GdHsp10 and GdHsp60 had high homology and were clustered with other Hsp10 and Hsp60 genes in insects which are highly relative with G. daurica based on morphologic taxonomy. The mRNA expression analysis by real-time PCR revealed that GdHsp10 and GdHsp60 were expressed at all development stages and in all tissues examined, but expressed highest in eggs and in adults' abdomen; both heat and cold stresses could induce mRNA expression of GdHsp10 and GdHsp60 in the 2nd instar larvae; the two Hsp genes were expressed from high to low with the extension of treatment time in G. daurica eggs exposed to freezing point. Overall, our study provides useful information to understand temperature stress responses of Hsp60 and Hsp10 in G. daurica, and provides a basis to further study functions of Hsp60/Hsp10 relative to thermotolerance and cold hardiness mechanism.

Mating triggers substantial changes in gene expression and leads to subsequent physiological and behavioral modifications. However, postmating transcriptomic changes responding to mating have not yet been fully understood. Here, we carried out RNA sequencing (RNAseq) analysis in the sweet potato whitefly, Bemisia tabaci MED, to identify genes in females in response to mating. We compared mRNA expression in virgin and mated females at 24 h. As a result, 434 differentially expressed gene transcripts (DEGs) were identified between the mated and unmated groups, including 331 up- and 103 down-regulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that many of these DEGs encode binding-related proteins and genes associated with longevity. An RT-qPCR validation study was consistent with our transcriptomic analysis (14/15). Specifically, expression of P450s (Cyp18a1 and Cyp4g68), ubiquitin-protein ligases (UBR5 and RNF123), Hsps (Hsp68 and Hsf), carboxylase (ACC-2), facilitated trehalose transporters (Tret1-2), transcription factor (phtf), and serine-protein kinase (TLK2) were significantly elevated in mated females throughout seven assay days. These combined results offer a glimpe of postmating molecular modifications to facilitate reproduction in B. tabaci females.

The intersex (ix) gene acts in concert with doublesex (dsx) at the end of the sex determination hierarchy to control somatic sexual differentiation in Drosophila melanogaster. Here, we report the Drosophila ix homolog in Bemisia tabaci (Btix) with differential splicing events. Four isoforms were found in B. tabaci adults, including two sex-specific transcripts (Btix F and Btix M). Knockdown of Btix had no measurable effects on female morphological phenotypes but reduced the expression of the vitellogenin gene and resulted in the production of significantly fewer eggs, a lower eclosion rate, and a shorter body size of female progeny in comparison with control females. These results increase our understanding of the genes underlying sex determination in B. tabaci and reveal a potential target for RNA interference-based pest management.

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