Inhibin beta A chain (Activin beta-A chain) (Erythroid differentiation protein) (EDF)
1_MPLLW 6_ LRGFL 11_ LASCW 16_ IIVRS 21_ SPTPG 26_ SEGHS 31_ AAPDC 36_ PSCAL 41_ AALPK 46_ DVPNS 51_ QPEMV 56_ EAVKK 61_ HILNM 66_ LHLKK 71_ RPDVT 76_ QPVPK 81_ AALLN 86_ AIRKL 91_ HVGKV 96_ GENGY 101_ VEIED 106_ DIGRR 111_ AEMNE 116_ LMEQT 121_ SEIIT 126_ FAESG 131_ TARKT 136_ LHFEI 141_ SKEGS 146_ DLSVV 151_ ERAEV 156_ WLFLK 161_ VPKAN 166_ RTRTK 171_ VTIRL 176_ FQQQK 181_ HPQGS 186_ LDTGE 191_ EAEEV 196_ GLKGE 201_ RSELL 206_ LSEKV 211_ VDARK 216_ STWHV 221_ FPVSS 226_ SIQRL 231_ LDQGK 236_ SSLDV 241_ RIACE 246_ QCQES 251_ GASLV 256_ LLGKK 261_ KKKEE 266_ EGEGK 271_ KKGGG 276_ EGGAG 281_ ADEEK 286_ EQSHR 291_ PFLML 296_ QARQS 301_ EDHPH 306_ RRRRR 311_ GLECD 316_ GKVNI 321_ CCKKQ 326_ FFVSF 331_ KDIGW 336_ NDWII 341_ APSGY 346_ HANYC 351_ EGECP 356_ SHIAG 361_ TSGSS 366_ LSFHS 371_ TVINH 376_ YRMRG 381_ HSPFA 386_ NLKSC 391_ CVPTK 396_ LRPMS 401_ MLYYD 406_ DGQNI 411_ IKKDI 416_ QNMIV 421_EECGC
1: Inhibins/activins are involved in regulating a number of diverse functions such as hypothalamic and pituitary hormone secretion, gonadal hormone secretion, germ cell development and maturation, erythroid differentiation, insulin secretion, nerve cell survival, embryonic axial development or bone growth, depending on their subunit composition
2: Activin A is a homodimer of INHBA that plays a role in several essential biological processes including embryonic development, stem cell maintenance and differentiation, haematopoiesis, cell proliferation and tissue fibrosis (PubMed:3194407, PubMed:16440334). Signals through type I (such as ACVR1B or ACVR1C) and type II receptors (such as ACVR2A, ACVR2B or BMPR2) which, upon ligand binding, phosphorylate SMAD2 and SMAD3 intracellular signaling mediators that form a complex with SMAD4, translocate to the nucleus and modulate gene expression (PubMed:10652306, PubMed:24018044). Can also activate alternative non-canonical intracellular signaling pathways including the p38 MAPK, extracellular signal-regulated kinases 1/2 (ERK1/2) and c-Jun N-terminal kinases (JNKs) to modulate cell migration and differentiation (PubMed:16440334). Alternatively, promotes osteoblastic differentiation via ACVRL1-SMAD1/5/9 pathway (PubMed:34948289). In addition, can engage the type I receptor ACVR1 to form an ACVR1-activin A-type II receptor non-signaling complex (NSC) that renders receptors unavailable for engagement with BMPs, hence resulting in an apparent inhibition of ACVR1-mediated BMP signaling (PubMed:26333933)
3: Inhibin A is a dimer of alpha/INHA and beta-A/INHBA that functions as a feedback regulator in the hypothalamic-pituitary-gonadal (HPG) axis. Inhibits the secretion of FSH from the anterior pituitary gland by acting on pituitary gonadotrope cells. Antagonizes activin A by binding to the proteoglycan, betaglycan, and forming a stable complex with and, thereby, sequestering type II activin receptors while excluding type I receptor