Receptor for BDNF –
**Core Concept**
Brain-Derived Neurotrophic Factor (BDNF) is a type of neurotrophin that plays a crucial role in neuronal growth, differentiation, and survival. BDNF binds to specific receptors on the surface of neurons to exert its effects.
**Why the Correct Answer is Right**
BDNF binds to its receptor, TrkB (Tropomyosin receptor kinase B), with high affinity. This binding activates the receptor, leading to the recruitment of adaptor proteins and the activation of downstream signaling pathways, including the PI3K/Akt and MAPK/ERK pathways. These pathways are involved in neuronal survival, differentiation, and plasticity.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because BDNF does not bind to the TrkA receptor, which is primarily associated with Nerve Growth Factor (NGF).
**Option B:** This option is incorrect because BDNF does not bind to the p75 receptor (also known as sortilin), which is a low-affinity receptor for BDNF but does not mediate its primary signaling effects.
**Option C:** This option is incorrect because BDNF does not bind to the Eph receptors, which are a family of receptor tyrosine kinases involved in axon guidance and other processes.
**Clinical Pearl / High-Yield Fact**
BDNF has been implicated in various neurological and psychiatric disorders, including depression, anxiety, and Alzheimer's disease. Dysregulation of BDNF signaling has been linked to impaired neuronal function and survival.
**Correct Answer: C. TrkB (Tropomyosin receptor kinase B)**