Question

you identify a new organelle in the cellwhich you determine is a hub for a certain class of protein called retrievers. you named it UMBC. you identify a short sequence which younthink is responsible for targeting these protein to UMBC. younname this sequence UTS.knowldege of other pathways the cell uses to target proteins to toher organelles, your predict that there is a second componentbreauired for proper targetting of proteins to UMBC in addition to UTS signal. which of the following best describes the identitiy of this other component?

a. an adapter proteins

b. clathrin

c. a small G protein

d. COP II coat protein

e. a receptor

component required*

Answer 1

The new cell organelle is identified and it contains a class of proteins called retrievers. These proteins are named as UMBC and these also contain signal sequence called UTS signal for targeting the protein. The targeting of proteins requires a second component additionally and it could be an adaptor protein. This is because the signal transducing adaptor proteins are accessory proteins to main proteins and required for signal transduction pathways. These adaptor proteins are composed of protein binding modules that link protein-binding partners together and form larger signaling complexes as in new cell organelle having hub of specific protein.

The clathrin is a protein forming coated vesicles for transport of proteins in a cell by exocytosis or by endocytosis. It allows cells to communicate, transfer nutrients, import signaling receptors and mediates an immune response between cells.

The small G proteins are small GTPases and hydrolase enzymes that hydrolyze GTP and found in the cytosol. These are homologous to the alpha subunit of heterotrimeric G-proteins and the Ras GTPases are an example of small G proteins.

The COPII coat protein is coatomer or vesicle coat protein that allows transport of proteins from endoplasmic reticulum to Golgi complex. The receptor component protein is a member of multi- protein complex and involved in G - protein coupled signal trasduction.

Therefore, the option a is correct.