Sp1 transcription factor (SP1) is a transcription factor involved in gene expression in the early development of an organism. It belongs to the Sp/KLF family of transcription factors. The SP1 transcription factor contains a zinc finger protein motif, by which it binds directly to DNA and enhances gene transcription. Targets of SP1 participate in a wide variety of cellular processes, including cell proliferation, adhesion and migration, anti-apoptosis, immune response, development and angiogenesis and many others [1].

SP1 controls inflammation by the activation of expression of Membrane-spanning 4-domains, subfamily A, member 1 (CD20), CD7 molecule (CD7) and CD34 molecule (CD34) [2], [3], [4], [5], [6].

Many SP1 targets are involved in cell adhesion and migration, such as: CD34, CD99 molecule (MIC2), carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), Endoglin, Biglycan, Collagen, type XVII, alpha 1 (BPAG2), Actin, alpha 1, skeletal muscle (ACTA1) and Actin, alpha 2, smooth muscle, aorta (ACTA2) [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20]. Notably, Endoglin, Biglycan and BPAG2 promote angiogenesis and developmental processes [21], [22], [23].

Troponin T type 3 (Beta TnTF), ACTA1, ACTA2, Myristoylated alanine-rich protein kinase C substrate (MARCKS) and Peptide YY participate in cytoskeleton remodeling and muscle contraction [24], [25], [26], [27], [28], [29], [30], [31].

SP1 influences cell metabolism by regulating of such enzymes and transporters, such as N-acetyltransferase 2 (NAT-2), BGAL, Tryptase delta 1 (Tryptase delta), Folate receptor 1 (FR-alpha), Solute carrier family 6 (neurotransmitter transporter, dopamine), member 3 (Dopamine transporter), Apolipoprotein C-III (APOC3), Retinol binding protein 1, cellular (RBP1), Lipoprotein, Lp(a) (APOLPA) and Major vault protein (MVP) [32], [33], [34], [35], [36], [37], [38], [39], [40], [41], [42], [43], [44], [45], [46], [47], [48], [49].

SP1 regulates gene transcription by activation of the expression of Progesterone receptor and Proteasome (prosome, macropain) subunit, alpha type, 4 (ChAF1 subunit A) [50], [51], [52], [53].

Progesterone receptor also participates in steroid synthesis and processes of development [54], [55].

SP1 may influence on neurotransmission by regulating of transcription of Glutamate receptor, metabotropic 2 (GRM2) [56], [57].

Known SP1 targets: Chorionic gonadotropin, beta polypeptide, beta polypeptide 1, beta polypeptide 2, beta polypeptide 5 and beta polypeptide 8 (CGB, CGB1, CGB2, CGB5 and CGB8) promote steroid synthesis which is necessary for process of reproduction [58], [59], [60].

SP1 can regulate cell proliferation by activation of transcription of Gastrin (Progastrin), Chromogranin A and Peptide YY [61], [62], [63], [64], [65].

In addition, Progastrin promotes protein translation and anti-apoptosis [66].

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