Complex sentence: Further studies have indicated roles for both G α and G βγ subunits in inhibition of calcium ion channels, and but much of the research to define the involvement of each subunit have not uncovered the specificity or mechanisms by which Ca 2 + channels are regulated.
Split into simpler sentences: Further studies have indicated roles for both G α and G βγ subunits in the inhibition of calcium ion channels. The research geared to defining the involvement of each subunit, however, has not uncovered the specificity or mechanisms by which Ca 2 + channels are regulated.