overall , calmodulin-stimulated phosphorylation and cmk ii levels were low in embryonic brain and high in adult brain but two specific changes in cmk ii were observed during development : ( 1 ) although cmk ii concentrations increased in both membrane and cytosolic fractions until day 23 the kinase was predominantly cytoplasmic ( approximately 75 % ) until day 23 , after which it became increasingly membrane bound so that by day 52 post-hatching the majority of cmk ii was present in the synaptic membrane fraction , and ( 2 ) the relative concentrations of the alpha- and beta-subunits changed from an alpha : beta-value of approximately 1:1 in the 19 day embryo to approximately 1:2 by 15 days post-hatch after which no further change was seen .
C0031715
phosphorylation
C0031727
kinase