Molecular cloning of cAMP-dependent protein kinase catalytic subunit isoforms from the lone star tick, Amblyomma americanum (L.)

• Published in: Insect biochemistry and molecular biology Vol. 29; no. 1; pp. 43 - 51
• Main Authors: Palmer, M.J., McSwain, J.L., Spatz, M.D., Tucker, J.S., Essenberg, R.C., Sauer, J.R.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 1999
• Subjects: Amblyomma americanum; Amino Acid Sequence; Animals; cAMP-dependent protein kinase; Catalytic Domain - genetics; Catalytic subunit; Cloning, Molecular; Cyclic AMP-Dependent Protein Kinases - genetics; Feeding Behavior; Isoenzymes - genetics; Ixodid; Ixodidae; Molecular Sequence Data; RNA, Messenger; Salivary gland; Salivary Glands - enzymology; Sequence Homology, Amino Acid; Tick; Ticks - enzymology; Catalytic subunit; Salivary gland; Tick; cAMP-dependent protein kinase; Ixodid
• ISSN: 0965-1748; 1879-0240
• DOI: 10.1016/S0965-1748(98)00103-9

The salivary glands of ixodid ticks are central to tick feeding and to survival during off-host periods. They produce and secrete a number of molecules critical to maintaining the complex host–vector interface and to maintaining osmotic balance. We have previously shown that a cyclic AMP-dependent protein kinase (cAPK) is involved in the mechanism of salivary gland secretion. We have now cloned cDNAs encoding three isoforms of the catalytic subunit (cAPK-C) of the cAPK from Amblyomma americanum, which are probably produced from alternative RNA processing of a single cAPK-C gene. The cDNAs contain unique N-termini of variable lengths that are linked to a common region containing the αA helix, catalytic core, and a C-terminal tail. The common region is highly similar to both insect and vertebrate cAPK-Cs. We have examined mRNA profiles in whole ticks and in isolated salivary glands throughout feeding and find that a single cAPK-C isoform is expressed in the salivary glands of both unfed and feeding females.