- Poster presentation
- Open Access
The elusive β2 subunit of sGC
- Sanchaita Sriwal Sonar1Email author,
- Thomas Eucker1 and
- Harald HHW Schmidt1, 2
https://doi.org/10.1186/1471-2210-5-S1-P53
© BioMed Central Ltd 2005
- Published: 16 June 2005
Keywords
- Knockout Mouse
- Major Organ
- Physiological Relevance
- Guanylyl Cyclase
- Enzyme Form
NO's major physiological receptor is the soluble guanylyl cyclase (sGC). sGC exist as heterodimers of 2 subunits, α/β. Heterodimerization between both the α and β subunit is essential for sGC's enzymatic activity. Five subunits, termed α1, α2, α2i, β1 and β2, have been identified so far; however, there are only two functional enzyme forms, α1/β1 and α2/β1, that appear to form in vivo at the protein level. The β2 sGC subunit is the most obscure isoform of all the subunits and its physiological relevance is until now unresolved. Here we clearly show a ubiquitous expression of sGCβ2 in wildtype mice. Cloning of this subunit revealed a 45 base pairs shorter splice variant in the 7th exon along with the predicted sGCβ2 mRNA. This shorter variant is expressed along with the sGCβ2 in all major organs. To further characterize the role of this subunit, we have generated a sGCβ2 knockout mice and back-crossed by speed-congenics. The heme NO binding domain (HNOB), comprising exons 5, 6 and 7 were deleted. Analysis of the knockout mice revealed no transcripts of sGCβ2 in all the major organs suggesting the sGCβ2 knockout mice are complete knockouts. These animals have been backcrossed by marker assisted backcrossing (speed congenics), with over 98 percent of the C57/BL6J (recipient) background incorporated. The phenotypic analysis of these knockout mice will help unravel the role of this subunit in the NO/cGMP cascade.