Cloning Three Harmonia axyridis (Coleoptera: Coccinellidae) Heat Shock Protein 70 Family Genes: Regulatory Function Related to Heat and Starvation Stress

Abstract Heat shock protein (HSP) is a very conservative group of proteins expressed in response to stress in organisms or cells in culture. There are four major HSP gene families in insects: small HSP, HSP60, HSP70, and HSP83. To gain insight into the various functions of the HSP70 family genes in response to stress in insects, two new HSP70 cDNAs were cloned from the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) (hereafter Harax when referring to genes, proteins, or cDNAs). HaraxHSP68 has an open reading frame (ORF) of 638 amino acids and an isoelectric point (pI) of 6.53. HaraxHSP70B has an ORF of 661 amino acids and a pI of 6.20. HaraxHSP70A, obtained in earlier work, has an ORF of 651 amino acids and a pI of 5.36. HSP70 proteins have the three signatures IDLGTTYSCVGV, IFDLGGGTFDVSIL, and IVLVGGSTRIPKIQ; the signature ATP/GTP binding site motif AEAYLG(K/T)T; and an MEEVD motif at the C terminus. The three HSP70 proteins do not have a high degree of similarity, ...