Anti-apoptotic factor is?
**Core Concept**
The question tests the understanding of **apoptosis** and its regulation by various factors. Apoptosis is a form of programmed cell death that plays a crucial role in maintaining tissue homeostasis and preventing disease. **Bcl-2** is a key protein family involved in this process.
**Why the Correct Answer is Right**
**Bcl-2** is an anti-apoptotic protein that inhibits cell death by regulating the **mitochondrial outer membrane permeabilization**. It does so by interacting with **pro-apoptotic** members of the Bcl-2 family, such as **Bax** and **Bak**, thereby preventing the release of **cytochrome c** into the cytosol.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it is not specified, and without the actual option text, we cannot determine its accuracy regarding anti-apoptotic factors.
**Option B:** Similarly, without the text, we cannot assess its correctness.
**Option C:** Again, lacking the specific text, its relevance to anti-apoptosis cannot be evaluated.
**Option D:** This option is also unspecified, making it impossible to comment on its correctness concerning anti-apoptotic factors.
**Clinical Pearl / High-Yield Fact**
Remember, **Bcl-2** overexpression is associated with various cancers, highlighting the importance of apoptosis regulation in oncogenesis. Understanding the balance between pro-apoptotic and anti-apoptotic signals is crucial for developing therapeutic strategies.
**Correct Answer:** D. Bcl-2.