os om es , ▁LI MP - 2 ▁was ▁cl oned ▁in ▁ 1 9 9 2 ▁by ▁two ▁groups , ▁one ▁isolated ▁LI MP - 2 ▁from ▁human ▁met ast atic ▁pan cre atic ▁is let ▁tum or ▁cells , ▁and ▁one ▁from ▁rat ▁li ver ▁l ys os om al ▁memb ran es . ▁LI MP - 2 ▁was ▁isolated ▁as ▁a ▁protein ▁of ▁approximate ▁mole cular ▁weight ▁ 8 5 ▁k Da , ▁synth es ized ▁from ▁a ▁prec ursor ▁of orm ▁of ▁approximately ▁ 7 7 ▁k Da . ▁The ▁weight ▁dis cre p ancy ▁between ▁its ▁theoretical ▁( 5 4 . 3 ▁k Da ) ▁and ▁observed ▁( 8 5 ▁k Da ) ▁is ▁due ▁to ▁the ▁presence ▁of ▁ 1 0 ▁high ▁man n ose - type ▁N - link ed ▁o lig os ac char ide ▁ch ains ▁in ▁the ▁human ▁form ▁of ▁this ▁protein , ▁compared ▁to ▁ 1 1 ▁in ▁mouse ▁and ▁rat . ▁LI MP - 2 ▁has ▁two ▁hydro ph ob ic ▁regions , ▁one ▁near ▁the ▁N - ter minus ▁and ▁one ▁near ▁the ▁C - ter minus , ▁as ▁well ▁as ▁a ▁short ▁is ole uc ine / le uc ine - rich ▁cy top las mic ▁tail ▁consisting ▁of ▁ 2 0 ▁am ino ▁ac ids ▁that ▁serves ▁as ▁the ▁l ys os om al ▁target ing ▁sequence . ▁LI MP - 2 ▁has ▁been ▁shown ▁to ▁be ▁expressed ▁in ▁brain , ▁heart , ▁li ver , ▁lung ▁and