CCAAT/enhancer-binding protein alpha (C/EBP alpha)
1_MESAD 6_ FYEAE 11_ PRPPM 16_ SSHLQ 21_ SPPHA 26_ PSSAA 31_ FGFPR 36_ GAGPA 41_ QPPAP 46_ PAAPE 51_ PLGGI 56_ CEHET 61_ SIDIS 66_ AYIDP 71_ AAFND 76_ EFLAD 81_ LFQHS 86_ RQQEK 91_ AKAAV 96_ GPTGG 101_ GGGGD 106_ FDYPG 111_ APAGP 116_ GGAVM 121_ PGGAH 126_ GPPPG 131_ YGCAA 136_ AGYLD 141_ GRLEP 146_ LYERV 151_ GAPAL 156_ RPLVI 161_ KQEPR 166_ EEDEA 171_ KQLAL 176_ AGLFP 181_ YQPPP 186_ PPPPS 191_ HPHPH 196_ PPPAH 201_ LAAPH 206_ LQFQI 211_ AHCGQ 216_ TTMHL 221_ QPGHP 226_ TPPPT 231_ PVPSP 236_ HPAPA 241_ LGAAG 246_ LPGPG 251_ SALKG 256_ LGAAH 261_ PDLRA 266_ SGGSG 271_ AGKAK 276_ KSVDK 281_ NSNEY 286_ RVRRE 291_ RNNIA 296_ VRKSR 301_ DKAKQ 306_ RNVET 311_ QQKVL 316_ ELTSD 321_ NDRLR 326_ KRVEQ 331_ LSREL 336_ DTLRG 341_ IFRQL 346_ PESSL 351_VKAMG
1: Transcription factor that coordinates proliferation arrest and the differentiation of myeloid progenitors, adipocytes, hepatocytes, and cells of the lung and the placenta. Binds directly to the consensus DNA sequence 5'-T[TG]NNGNAA[TG]-3' acting as an activator on distinct target genes (PubMed:11242107). During early embryogenesis, plays essential and redundant functions with CEBPB. Essential for the transition from common myeloid progenitors (CMP) to granulocyte/monocyte progenitors (GMP). Critical for the proper development of the liver and the lung (By similarity). Necessary for terminal adipocyte differentiation, is required for postnatal maintenance of systemic energy homeostasis and lipid storage (By similarity). To regulate these different processes at the proper moment and tissue, interplays with other transcription factors and modulators. Down-regulates the expression of genes that maintain cells in an undifferentiated and proliferative state through E2F1 repression, which is critical for its ability to induce adipocyte and granulocyte terminal differentiation. Reciprocally E2F1 blocks adipocyte differentiation by binding to specific promoters and repressing CEBPA binding to its target gene promoters. Proliferation arrest also depends on a functional binding to SWI/SNF complex (PubMed:14660596). In liver, regulates gluconeogenesis and lipogenesis through different mechanisms. To regulate gluconeogenesis, functionally cooperates with FOXO1 binding to IRE-controlled promoters and regulating the expression of target genes such as PCK1 or G6PC1. To modulate lipogenesis, interacts and transcriptionally synergizes with SREBF1 in promoter activation of specific lipogenic target genes such as ACAS2. In adipose tissue, seems to act as FOXO1 coactivator accessing to ADIPOQ promoter through FOXO1 binding sites (By similarity)
2: Can act as dominant-negative. Binds DNA and have transctivation activity, even if much less efficiently than isoform 2. Does not inhibit cell proliferation (PubMed:14660596)
3: Directly and specifically enhances ribosomal DNA transcription interacting with RNA polymerase I-specific cofactors and inducing histone acetylation