Cloning and expression analysis of a cDNA that encodes a leech hemerythrin

We report the cDNA sequence of a leech hemerythrin. A cDNA was isolated fro m a Theromyzon tessulatum cDNA library and encodes a 120 amino acid protein of about 14 kDa, The predicted protein contains the hemerythrin signature sequence and the iron ligand residues previously identified in crystal stru ctures of hemerythrin and myohemerythrin. The protein displayed the highest identity to myohemerythrin, a non-heme iron-binding protein described in s ipunculids. Expression analysis indicated that the mRNA is widely expressed in leech and is stage specific in appearance, being absent after the two f irst blood meals, appearing after the last blood meal during the period pre ceding oogenesis and disappearing after egg laying. (C) 2001 Elsevier Scien ce B.V. All rights reserved.