▁protein ▁alpha - 7 ▁integr in . ▁Al pha - 7 ▁integr in ▁is ▁ 1 2 8 . 9 ▁k Da ▁in ▁mole cular ▁weight ▁and ▁ 1 1 8 1 ▁am ino ▁ac ids ▁in ▁length . ▁Integr ins ▁are ▁heter od imer ic ▁integral ▁memb rane ▁prote ins ▁composed ▁of ▁an ▁alpha ▁chain ▁and ▁a ▁beta ▁chain . ▁Al pha - 7 ▁integr in ▁under go es ▁post - trans l ational ▁cle av age ▁within ▁the ▁ext rac ell ular ▁domain ▁to ▁yield ▁dis ulf ide - link ed ▁light ▁and ▁heavy ▁ch ains ▁that ▁join ▁with ▁beta ▁ 1 ▁to ▁form ▁an ▁integr in ▁that ▁bind s ▁to ▁the ▁ext rac ell ular ▁matrix ▁protein ▁l amin in - 1 . ▁The ▁primary ▁binding ▁partners ▁of ▁alpha - 7 ▁integr in ▁are ▁l amin in - 1 ▁( alpha 1 - beta 1 - gamma 1 ), ▁l amin in - 2 ▁( alpha 2 - beta 1 - gamma 1 ) ▁and ▁l amin in - 4 ▁( alpha 2 - beta 2 - gamma 1 ). ▁Al pha - 7 / beta - 1 ▁is ▁the ▁major ▁integr in ▁complex ▁expressed ▁in ▁differenti ated ▁mus cle ▁cells . ▁ ▁Sp lice ▁variants ▁of ▁alpha - 7 ▁integr in ▁that ▁differ ▁in ▁both ▁the ▁ext rac ell ular ▁and ▁cy top las mic ▁domains ▁exist ▁in ▁the ▁mouse ▁and ▁are ▁development ally ▁reg ulated ▁in ▁mouse ▁and ▁rat ▁mus cle ▁t issue . ▁The ▁X 1 /