Searching for the physiological functions of Copeptin

Authors

• B Campbell
• M Bodogai
• X Wang
• RA McDevitt
• K Konda
• H Ishikawa-Ankerhold
• A Biragyn

Abstract

Arginine vasopressin (AVP) secreted by hypothalamic neurons controls water resorption and blood pressure via its receptors in the kidneys and in vasculature, respectively. Our group has found that AVP receptors are present in hematopoietic progenitor cells. We have shown a novel physiological role for AVP in stimulating red blood cell precursors in mice. We also showed that the lack or decrease of AVP in patients results in anemia. While many functions of vasopressin have been described, so far no physiological function has been found for AVP's C-terminal glycopeptide, Copeptin (CP). CP is well preserved through many species suggests an important physiological function.
Because of the novel effects of AVP on bone marrow (BM) cells, we decided to study a potential role of CP modifying hematopoiesis. We performed in vivo studies by injecting CP in mice. Our preliminary data suggest that CP is also involved in regulating hematopoietic progenitors. Following i.p injection we observed effects in peripheral blood on the number of platelets. Next, we studied platelet aggregation upon CP treatment. Our results indicate that like vasopressin, CP receptor/s are also present on platelets. To identify the specific receptor/s responsible for these responses we performed receptor-ligand binding assays using a biotinylated CP. Using a pull-down approach we identified different bands corresponding to the proteins binding to labelled CP. Next, we will use mass spectrometry, to identify these potential targets as CP receptor/s.
Once we find the putative receptor, we hope to start to understand the interaction between CP and its receptor/s.

Scientific Focus Area: Stem Cell Biology

This page was last updated on Monday, September 25, 2023