GDF-5 Protein, Mouse

GDF-5 Protein plays a crucial role in bone and cartilage formation, orchestrating differentiation in chondrogenic tissue through dual pathways. It positively regulates chondrogenic differentiation by binding with high affinity to BMPR1B and with lower affinity to BMPR1A, triggering the phosphorylation of the SMAD1-SMAD5-SMAD8 complex and subsequent SMAD protein signaling transduction. Simultaneously, it exerts a negative regulatory effect on chondrogenic differentiation through interaction with NOG. Additionally, GDF-5 is essential for preventing excessive muscle loss upon denervation, a function mediated by phosphorylated SMAD1/5/8. The protein also binds bacterial lipopolysaccharide (LPS) and mediates LPS-induced inflammatory responses, including TNF secretion by monocytes. Structurally, GDF-5 forms homodimers linked by disulfide bonds and interacts with serine proteases HTRA1 and HTRA3. It may also form a complex with CXCR4, HSP90AA1, and HSPA8 following LPS binding. Furthermore, GDF-5 interacts with high affinity with NOG to inhibit chondrogenesis and with BMPR1B and BMPR1A to positively regulate chondrocyte differentiation through SMAD-dependent signaling. Additionally, it engages in interactions with FBN1 and FBN2.