Final answer:
The Rho family, part of the RAS superfamily, includes RhoA, RhoB, and RhoC, which are all involved in regulating the actin cytoskeleton and various cellular processes. Each of these proteins can be activated by GEFs and inactivated by GAPs, crucial for their functions in cells. Option 4) All of the above is the correct answer.
Step-by-step explanation:
The Rho family is part of the RAS superfamily of small GTPases, which are involved in multiple cellular processes such as cell proliferation, cell morphology, and cell migration. When it comes to the Rho family of the RAS superfamily, the examples provided in the question are all correct. Specifically, the members are RhoA, RhoB, and RhoC. These proteins are closely related and share similar functions in regulating the actin cytoskeleton, which is critical for the aforementioned cellular processes. They play vital roles in various signaling pathways that dictate cell behavior.
RhoA is well-known for its role in the formation of stress fibers and focal adhesions, making it essential for maintaining cell shape and motility. RhoB has a shorter half-life compared to RhoA and RhoC and is implicated in endosome trafficking and modulating cellular responses to DNA damage. RhoC shares a high degree of homology with RhoA and is involved predominantly in cell motility and possibly in metastasis of cancer cells.
Each member of the Rho family can be activated by specific guanine nucleotide exchange factors (GEFs) and can be inactivated by GTPase-activating proteins (GAPs). This activation-inactivation cycle is crucial for the temporal and spatial regulation of Rho proteins' functions. In summary, all of the above options (1) RhoA, (2) RhoB, and (3) RhoC are examples of the Rho family of the RAS superfamily.