A MEMBER OF THE HSP70 GENE FAMILY FROM THE MEDITERRANEAN FRUIT-FLY, CERATITIS-CAPITATA

A gene from the Mediterranean fruit fly (Medfly) Ceratitis capitata, b elonging to the hsp70 family of genes, has been cloned and characteriz ed. This gene appears to be an example of a heat shock cognate (hsc) g ene based on a variety of structural and functional criteria, The heat shock cognate genes serve critical roles in chaperoning of cellular p roteins, and they are expressed in a more constitutive manner compared to the inducible heat shock genes, We determined the sequence of the entire coding region of this gene (designated Cerhsc1) together with 5 ' and 3' flanking regions. The coding region exhibits specific structu ral features that are characteristic of the subclass of heat shock gen es producing proteins localized to the cytosol. The 5' regulatory regi on of Cerhsc1 contains only the minimal array of canonical heat shock element sequences, a phenomenon commonly seen in heat shock cognates. Abundant transcripts are detected from this gene in adult tissue compa red to the larval stage. In larval tissue, heat shock appears to produ ce only a slight increase in the level of transcripts detected. Based on overall structure and function, this Medfly gene appears to be an o rtholog of heat shock cognate gene 4 (Drohsc4) of Drosophila melanogas ter.