Abstract
Purpose: :
Neuroglobin is a newly discovered nervous system specific O2-binding protein, and it’s concentration in the retina is 100-fold higher than that in total brain extracts. Na+, K+-ATPase beta 2 subunit was identified to have interaction with neuroglobin by east two hybrid technique in vitro. This study was designed to investigate the expressions and protein interaction between neuroglobin and Na+, K+-ATPase beta 2 subunit in vivo in rat retinas.
Methods: :
The polyclonal antibody against Na+, K+-ATPase beta 2 subunit and anti-neuroglobin monoclonal antibodies were produced using Japanese adult male rabbits and immunizing Balb/c mice respectively. We detected the expression of the above two proteins by gel electrophoresis and western blot skills and the interaction was proved by co-immunoprecipitation test in vivo.
Results: :
The homemade antiserums could detect both of the neuroglobin and Na+, K+-ATPase beta 2 subunit proteins which expressed in rat retinas. The apparent molecular mass of native neuroglobin in retina is 17 kDa and for Na+, K+-ATPase beta 2 subunit, it is 45kDa. Immunoprecipitation product was detected by using Western blot with either anti-neuroglobin monoclonal antibody or polyclonal antibody against Na+, K+-ATPase beta 2 subunit.
Conclusions: :
Neuroglobin, an oxygen-binding respiratory protein, is synthesized at a high level in the rat retina and there is an interaction between the former protein and the β2 subunit of Na+-K+-ATPase, of which both might attend the activities of oxygen supply or consumption and maintain the ion homeostasis in retinas.
Keywords: neuroprotection • retina • hypoxia