Semaphorin 7A, GPI membrane anchor (John Milton Hagen blood group) (SEMA7A) also known as CD108 (Cluster of Differentiation 108), is a human gene. [5]
SEMA7A is a membrane-bound semaphorin that associates with cell surfaces via a glycosylphosphatidylinositol (GPI) linkage. SEMA7A is also known as the John-Milton-Hagen (JMH) blood group antigen, an 80-kD glycoprotein expressed on activated lymphocytes and erythrocytes.[supplied by OMIM] [5] SEMA7A is expressed in various adult tissues such as adipose, colon, esophagus, heart, brain, spleen, testis, lung, ovary, and uterus. [6]
SEMA7A promotes axonal growth and is involved in mesoderm derived somite formation. Murine embryonic Sema7A expression is highest on day 7, which is indicative of its role on the differentiation of germ layer structure. [7] Embryonic Sema7A expression is noticeable at all developmental stages as well as in the newborn and adult thymus, indicative of a development T-cell role. [7] In wild type neurons, addition of Sema7A under in vitro conditions promotes elongation and branching in a dose dependent manner. [8] Unlike the majority of semaphorins, SEMA7A enhances axonal growth and is imperative for proper embryonic axonal tract formation. [9] Limited expression of SEMA7A is found in the hindbrain as opposed to an abundance of SEMA7A expression found in both the cranial and trunk neural crest cells, which indicates an involvement in migration and differentiation. [10] Sema7A -/- mice show defects in olfactory tract development. [11]
In normal breast tissue, mRNA expression of SEMA7A is low or not expressed, but activation to re-express SEMA7A occurs in these adult tissues to cause pleiotropic effects which increase tumorigenesis. [12] [13] Tumor cell growth, EMT, lung metastasis and angiogenesis have been linked to increased Sema7a expression in murine models. [14] [15] [16] Increased SEMA7A expression correlates with poor prognosis in breast cancer patients. [13] Tumors increase SEMA7A expression in an involuting environment, but knockout of SEMA7a in mouse models undergoing involution decreases lymphangiogenesis. [17]
This protein is known to have eight variants in the extracellular region: seven lie within the Sema domain and one within the PSI domain.[ citation needed ]
This protein forms dimers.[ citation needed ]
This protein acts as a receptor for the malaria parasite Plasmodium falciparum .
Keratin 18 is a type I cytokeratin. It is, together with its filament partner keratin 8, perhaps the most commonly found products of the intermediate filament gene family. They are expressed in single layer epithelial tissues of the body. Mutations in this gene have been linked to cryptogenic cirrhosis. Two transcript variants encoding the same protein have been found for this gene.
T-box transcription factor T, also known as Brachyury protein, is encoded for in humans by the TBXT gene. Brachyury functions as a transcription factor within the T-box family of genes. Brachyury homologs have been found in all bilaterian animals that have been screened, as well as the freshwater cnidarian Hydra.
Cripto is an EGF-CFC or epidermal growth factor-CFC, which is encoded by the Cryptic family 1 gene. Cryptic family protein 1B is a protein that in humans is encoded by the CFC1B gene. Cryptic family protein 1B acts as a receptor for the TGF beta signaling pathway. It has been associated with the translation of an extracellular protein for this pathway. The extracellular protein which Cripto encodes plays a crucial role in the development of left and right division of symmetry.
Glypicans constitute one of the two major families of heparan sulfate proteoglycans, with the other major family being syndecans. Six glypicans have been identified in mammals, and are referred to as GPC1 through GPC6. In Drosophila two glypicans have been identified, and these are referred to as dally and dally-like. One glypican has been identified in C. elegans. Glypicans seem to play a vital role in developmental morphogenesis, and have been suggested as regulators for the Wnt and Hedgehog cell signaling pathways. They have additionally been suggested as regulators for fibroblast growth factor and bone morphogenic protein signaling.
Melanotransferrin is a protein that in humans is encoded by the MFI2 gene. MFI2 has also recently been designated CD228.
Neuropilin-1 is a protein that in humans is encoded by the NRP1 gene. In humans, the neuropilin 1 gene is located at 10p11.22. This is one of two human neuropilins.
Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) also known as CD66c, is a member of the carcinoembryonic antigen (CEA) gene family..
Semaphorin-3A is a protein that in humans is encoded by the SEMA3A gene.
Semaphorin-4D (SEMA4D) also known as Cluster of Differentiation 100 (CD100), is a protein of the semaphorin family that in humans is encoded by the SEMA4D gene.
Phosphatidylinositol-glycan-specific phospholipase D is an enzyme that in humans is encoded by the GPLD1 gene.
Prostate stem cell antigen is a protein that in humans is encoded by the PSCA gene.
GPI transamidase component PIG-T is an enzyme that in humans is encoded by the PIGT gene.
Semaphorin-3F is a protein that in humans is encoded by the SEMA3F gene.
Semaphorin-3B is a protein that in humans is encoded by the SEMA3B gene.
GPI-anchor transamidase is an enzyme that in humans is encoded by the PIGK gene.
Semaphorin-3C is a protein that in humans is encoded by the SEMA3C gene.
Glycosylphosphatidylinositol anchor attachment 1 protein is a protein that in humans is encoded by the GPAA1 gene.
Semaphorin-4A is a protein that in humans is encoded by the SEMA4A gene.
Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) also known as CD66e, is a member of the carcinoembryonic antigen (CEA) gene family.
Transcription factor AP-2 gamma also known as AP2-gamma is a protein that in humans is encoded by the TFAP2C gene. AP2-gamma is a member of the activating protein 2 family of transcription factors.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.