Work done by Julián Hillyer, Tania Estévez-Lao, Lisa Funkhouser and Vivian Aluoch was published today in the journal Insect Molecular Biology.  In this article, we performed molecular and physiological experiments to show that:

1. 1)Anopheles gambiae Corazonin (CRZ) is a single copy gene and is alternatively spliced, with the only difference between the transcripts occurring in the 5’ untranslated region.
   

2. 2)An. gambiae encodes the most common form of the corazonin peptide: [Arg7]-corazonin.
   

3. 3)Developmental expression of An. gambiae Corazonin (CRZ) and the Corazonin Receptor (RCRZ) follows a bimodal distribution, with highest mRNA levels in 2nd instar larvae and during the pupa to adult transition.
   

4. 4)In vivo injection of corazonin peptide or reduction in CRZ and CRZ/RCRZ levels by RNA interference failed to detect a significant role for this neuropeptide in modulating mosquito heart physiology.
   

CITATION:

Hillyer, J.F., T.Y. Estévez-Lao, L.J. Funkhouser, and V.A. Aluoch. 2012. Anopheles gambiae corazonin: gene structure, expression and effect on mosquito heart physiology. Insect Molecular Biology. 21(3):343-355.

DOI: 10.1111/j.1365-2583.2012.01140.x

To see the article click HERE.  Can’t see it? Send an Email pdf reprint request.

ARTICLE ABSTRACT:

Haemolymph flow in mosquitoes is primarily driven by the contraction of a dorsal vessel that is subdivided into an abdominal heart and a thoracic aorta. The factors that regulate mosquito heart contractions are not understood, but in other insects heart physiology is partially controlled by several neurohormones. One of these is corazonin, a neuropeptide initially discovered because of its cardioacceleratory activity in the cockroach Periplaneta americana. In the present study, we describe the corazonin gene and transcript structure in the mosquito Anopheles gambiae, characterize its developmental expression, and test its role in modulating heart physiology. We show that the A. gambiae corazonin gene encodes the most common form of the corazonin peptide ([Arg7]-corazonin) and that it is alternatively spliced, with the only difference between the transcripts occurring in the 5′ untranslated region. Analysis of the developmental expression of corazonin and the corazonin receptor revealed that transcription of both follows a bimodal distribution, with highest mRNA levels in 2nd instar larvae and during the pupa to adult transition. Finally, experiments where mosquitoes were injected with various doses of corazonin and experiments where the transcription of corazonin and the corazonin receptor were reduced by RNA interference failed to detect a significant role for this neuropeptide in modulating mosquito heart physiology.

This work was funded by National Science Foundation grant IOS-1051636 to Julián Hillyer. The Vanderbilt Center for Science Outreach supported high school student Vivian Aluoch through a fellowship from the Vanderbilt University Research Internship Program (since renamed Research Experience for High School Students).

* This news story was modified on 5/10/2012 to include the full citation of the article once it was assigned to an issue.