Question

(3pts) You fused an NLS (nuclear localization sequence) onto the C-terminal side of a lysosomal protein. However, instead of the protein entering the nucleus, the mutant protein is still delivered to the lysosome. Explain the molecular mechanism of why the fused NLS did not change the protein’s destination. Please be very detailed (8 sentence max)

Answer 1

The fused NLS did not changed the protein localization because the destined protein was for lysosomes.Protein targeted to lysosome has specific mannose-6-phosphate tag which gets linked to Oligsacchrides present on the protein surface in cis golgi.This mannose-6-phosphate tagged protein gets recognised by specific receptors on the trans golgi membrane.This receptor gets packed in clathrin coat protein. Then these identify the enzymes hydrolases in the lysosome and due to low pH the protein gets released in lysosme.So that mannose6 tag needed to be remove so that protein doesnt enter lysosome.