Question

c. A protein called Merlin (Nf2) has been identified as a tumor suppressor. An explanation for its role as a tumor suppressor is likely found in Merlin’s influence on vesicular trafficking! Researchers labeled a v-SNARE with green florescent protein to monitor vesicular trafficking in cells lacking merlin protein. Why would monitoring a v-SNARE allow researchers to track vesicular trafficking? Rubric (2): explanation shows understanding of where vSNARES are present in the cell.

Answer: Once a vesicle is formed with its cargo inside, there is a v-snare protruding from the vesicle. By labeling the v-snare, the researchers could monitor the path of the vesicle from when the vesicle is released by coat assembly to when the v-snare and t-snare interact and fuse the vesicle and target membrane. This occurs during vesicular transport from the donor membrane to the target membrane.

e. The researchers found that anterograde vesicular transport was slower in cells with no Merlin protein present. This suggests that Merlin regulates motor protein function. Which type of motor protein might be affected by Merlin? Rubric (2): correct motor protein.

f.   Merlin slowed vesicular transport by influencing motor protein function. Hypothesize as to how Merlin might slow the walking of a motor protein. Rubric (2): all plausible answers get full points!

Answer 1

v-SNARE- is Vesicle SNARE. These proteins are incorporated into the membrane of transport vesicles in the budding process. SNARE is a protein complex which mediates vesicle fusion.

Monitoring v-SNARE will allow researchers to track vesicular trafficking because during membrane fusion v-SNARE and t-SNARE interact and form a SNARE complex. After the interaction of v-SNARE and t-SNARE, the vesicle and the target membrane are fused. Hence the transport path can be monitored by labeling the v-SNA

So the right answer is Once a vesicle is formed with its cargo inside, there is a v-snare protruding from the vesicle. By labeling the v-snare, the researchers could monitor the path of the vesicle from when the vesicle is released by coat assembly to when the v-snare and t-snare interact and fuse the vesicle and target membrane. This occurs during vesicular transport from the donor membrane to the target membrane.