Microtubule-associated protein 2

Microtubule-associated protein 2 is a protein in humans that is encoded by the MAP2 gene.^[5][6]

MAP2
Identifiers
Aliases	MAP2, MAP2A, MAP2B, MAP2C, microtubule associated protein 2, MAP-2
External IDs	OMIM: 157130; MGI: 97175; HomoloGene: 1779; GeneCards: MAP2; OMA:MAP2 - orthologs
Gene location (Human) Chr. Chromosome 2 (human)[1] Band 2q34 Start 209,424,058 bp[1] End 209,734,118 bp[1]
Gene location (Mouse) Chr. Chromosome 1 (mouse)[2] Band 1 C3|1 33.49 cM Start 66,214,432 bp[2] End 66,481,742 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in Brodmann area 23 endothelial cell superior vestibular nucleus entorhinal cortex pons pars compacta parietal lobe postcentral gyrus middle temporal gyrus pars reticulata Top expressed in anterior amygdaloid area ventromedial nucleus nucleus accumbens lateral septal nucleus superior frontal gyrus paraventricular nucleus of hypothalamus olfactory tubercle dorsomedial hypothalamic nucleus olfactory bulb subiculum More reference expression data BioGPS More reference expression data
Gene ontology Molecular function tubulin binding protein binding structural molecule activity dystroglycan binding calmodulin binding microtubule binding tau protein binding Cellular component nucleolus microtubule microtubule associated complex cytoskeleton cytoplasm cytosol dendrite cell projection intracellular anatomical structure postsynaptic density nuclear periphery neuron projection soma dendritic shaft cell body CA3 pyramidal cell dendrite dendrite cytoplasm axon initial segment axon hillock dendritic growth cone main axon dendritic branch basal dendrite primary dendrite distal dendrite apical distal dendrite dendritic filopodium proximal dendrite proximal neuron projection Biological process neuron projection development microtubule cytoskeleton organization microtubule bundle formation dendrite morphogenesis central nervous system neuron development axonogenesis dendrite development establishment of cell polarity regulation of axonogenesis cellular response to organic substance negative regulation of axon extension regulation of microtubule polymerization negative regulation of microtubule polymerization positive regulation of anterograde dense core granule transport regulation of organelle transport along microtubule positive regulation of anterograde synaptic vesicle transport negative regulation of microtubule binding Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 4133 17756 Ensembl ENSG00000078018 ENSMUSG00000015222 UniProt P11137 P20357 RefSeq (mRNA) NM_001039538 NM_002374 NM_031845 NM_031846 NM_031847 NM_001363910 NM_001363911 NM_001363913 NM_001039934 NM_008632 NM_001310634 RefSeq (protein) NP_001034627 NP_002365 NP_114033 NP_114035 NP_001350839 NP_001350840 NP_001350842 NP_001362403 NP_001362422 NP_001362423 NP_001362424 NP_001362425 NP_001362426 NP_001362427 NP_001362428 NP_001362429 NP_001362430 NP_001362431 NP_001362432 NP_001362433 NP_001362434 NP_001362435 NP_001362436 NP_001362437 NP_001362438 NP_001362439 NP_001362455 NP_001362456 NP_001362457 NP_001362458 NP_001362459 NP_001362460 NP_001362461 NP_001362462 NP_001362463 NP_001362464 NP_001362465 NP_001362466 NP_001362467 NP_001362468 NP_001362469 NP_001362470 NP_001362471 NP_001362472 NP_001362473 NP_001362474 NP_001362475 NP_001362477 NP_001362480 NP_001362481 NP_001362482 NP_001362483 NP_001362484 NP_001362485 NP_001362486 NP_001362487 NP_001362488 NP_001362512 NP_001035023 NP_001297563 NP_032658 Location (UCSC) Chr 2: 209.42 – 209.73 Mb Chr 1: 66.21 – 66.48 Mb PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse

Function

This gene encodes a protein that belongs to the microtubule-associated protein family. The proteins of this family were originally isolated since they copurify with tubulin in polymerization experiments: tubulin in cell extracts can be made to polymerize to produce microtubules (MT) under the influence of heat and the addition of GTP, and the MT can then be collected by centrifugation. When this is done a series of microtubule associated proteins are collected along with the MT and can be detected by SDS-PAGE and other methods. Brain extracts are rich in several of these proteins, MAP2 being one of these. The single MAP2 gene produces four major transcripts producing four proteins, MAP2A, MAP2B, MAP2C and MAP2D. MAP2A and MAP2B are very high molecular weight proteins, with apparent molecular weight on SDS-PAGE about 250 kDa, while MAP2C and MAP2D are much lower molecular weight forms with apparent SDS-PAGE size about 70 kDa.^[7] All forms of MAP2 share a common core sequence which includes MT binding domains, 18 amino acid sequences which are found in other MT associated proteins such as MAP Tau and MAP1B. The MAP2 isoforms are thought to be involved in MT assembly, which is an essential step in neuritogenesis. MAP2 serves to stabilize MT growth by crosslinking MT with intermediate filaments and other MTs. MAP2 isoforms are neuron-specific cytoskeletal proteins enriched in dendrites and perikarya, implicating a role in determining and stabilizing neuronal morphology during neuron development. As a result antibodies to MAP2 are widely used to identify neuronal cells and trace dendritic processes in experimental contexts.

Interactions

MAP2 has been shown to interact with Grb2,^[8][9] NEFL^[10] and MYO7A.^[11] All MAP2 isoforms bind to microtubules.

Neurons were grown in tissue culture and stained with antibody to MAP2 protein in green and MAP tau in red using the immunofluorescence technique. MAP2 is found only in dendrites and perikarya, while tau is found not only in the dendrites and perikarya but also in axons. As a result, axons appear red while the dendrites and perikarya appear yellow, due to superimposition of the red and green signals. DNA is shown in blue using the DAPI stain which highlights the nuclei. Image courtesy EnCor Biotechnology Inc.