Phosphorylation of Smooth Muscle Myosin Heavy Chains

Phosphorylation of Smooth Muscle Myosin Heavy Chains 

All smooth muscle 204-kDa HCs examined to date, with the notable exception of the chicken gizzard 204-kDa HC, contain a consensus sequence for casein 

Polyclonal antibodies that detect both the 204- and 200-kDa HCs were raised in rabbits using purified bovine aortic smooth muscle myosin, which is a 1 1 mixture of both isoforms as antigens. These antibodies have approximately equal affinity for HC204 and HC200 (Kelley and Adelstein, 1990). Immunoblot analysis of smooth muscle HMM and LMM using the 50% ammonium sulfate immunoglobulin (IgG) fraction revealed that practically all the epitopes were located in the LMM region (Christine A. Kelley, unpublished results, NHLBI). 

Using similar techniques, antibodies were generated to the seven-amino-acid insert that is introduced by alternative splicing of pre-mRNA into the head region of a number of visceral smooth muscle myosins (Kelley et al., 1993) (see Fig. 7). Since these antibodies are raised to only seven amino acids, the titer of the serum obtained from different rabbits has not been consistently high. 

ANALYSIS OF THE PRIMARY SEQUENCE OF SMOOTH MUSCLE MYOSIN HEAVY CHAIN 

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B. Phosphorylation of Smooth Muscle Myosin Heavy Chains... 

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