Disease relevance of MAP2

• Cerebolysin protected MAP2 in primary neuronal cultures after a brief histotoxic hypoxia and in a rat model of acute brain ischemia [1].
• Differential distribution of two microtubule-associated proteins, MAP2 and MAP5, during chick dorsal root ganglion development in situ and in culture [2].
• With Western blotting and immunohistochemical techniques it has been demonstrated that the drug clearly increased MAP2 abundance after histotoxic hypoxia [3].
• The optimum quantity of MAP1 and MAP2 required to coat the wells of the ELISA plate was 5 ng/ml, whereas the amount of purified IBDV whole viral antigen was 500 ng/ml, indicating the high efficiency of MAPs [4].
• We describe the isolation of a set of overlapping cDNAs encoding mouse microtubule associated protein 2 (MAP2), using an anti-MAP antiserum to screen a mouse brain cDNA expression library cloned in bacteriophage lambda gt11 [5].

Psychiatry related information on MAP2

• Neuronal cytoskeletal proteins like the microtubule associated protein 2 (MAP2) are objected to pathological proteolysis in case of Alzheimer's disease and brain ischemia [1].

High impact information on MAP2

• The microheterogeneity of MAP2 is therefore ascribable either to alternative splicing within a single gene, or to posttranslational modification(s), or both [5].
• Upon subcloning this non-overlapping fragment into plasmid expression vectors, a fusion protein was synthesized that was immunoreactive with an anti-MAP2 specific antiserum [5].
• Though brain contained abundant quantities of MAP2 mRNA, no corresponding sequences were detectable in RNA prepared from liver, kidney, spleen, stomach, or thymus [5].
• The modified MAPs (especially enriched for MAP2) were fully active in promoting tubulin polymerization in vitro and readily associated with cytoplasmic filaments when microinjected into living cultured cells [6].
• Controls showed that the antiserum could react on SDS gels with MAP 2 from purified chick brain microtubules [7].

Biological context of MAP2

• Immunohistochemical experiments for MAP2 revealed that, compared with controls, NaCN and, to a much higher extent, IM treatment resulted in a loss of immunoreactivity in neurites due to progressing cell death [8].
• Only the phosphorylation produced by embryonic MAP2 kinase can change the affinity of MAP2 by microtubules [9].
• 3) The binding of truncated constructs of mouse MAP2 protein suggests that a domain of MAP2 conferring cooperativity is located in or near the MT binding site near the carboxyl terminus [10].
• The inclusion of 67 mM-NaCl dissociates the MAP2-tubulin oligomers, and restricts the assembly to the MAP2-dependent addition and loss of tubulin dimers, such that the assembly kinetics approximate to a simple pseudo-first-order reaction [11].
• Binding of the antibodies was saturable and the ELISA signal was proportional to the number of immunoreactive cells comprising 2-4% and 16% of the total cell number with opsin and MAP2 antibodies, respectively [12].

Anatomical context of MAP2

• The E10-11 patterns run counter to an apparent gradient in dendrite density, as indicated by microtubule associated protein 2 (MAP2) immunolabeling [13].
• Nerve cells were found to mature during the first 7 days in culture, as indicated by the presence and developmental pattern of the relative amount of dendritic-specific microtubule-associated protein type 2 (MAP2) [14].
• In this study we have analyzed the expression and localization of MAP2 and MAP5 isoforms during chick dorsal root ganglia development in vivo, and in cell culture [2].
• By immunocytochemistry, MAP2 isoforms were mainly located in the neuronal perikarya and in the proximal portion of axons, but could not be localized to distal axonal segments, nor in sciatic nerve at any developmental stage [2].
• A microtubule-associated protein (MAP2) kinase restores microtubule motility in embryonic brain [9].

Associations of MAP2 with chemical compounds

• Effects of NaCN and ionomycin on neuronal viability and on the abundance of microtubule-associated proteins MAP1, MAP2, and tau in isolated chick cortical neurons [8].
• In other experiments the protein synthesis of Cerebrolysin treated and untreated cells was blocked with cycloheximide at that moment when all cells exhibited the same MAP2 content [1].
• Ontogeny of MAP2 and GFAP antigens in primary cultures of embryonic chick brain. Effect of substratum, oxygen tension, serum and Ara-C [14].
• We have identified this activity with a kinase, embryonic MAP2 kinase (M(r) = 100,000), which phosphorylates MAP2 at serine amino acid residues [9].
• The chick brain microtubule-associated protein MAP2 can be phosphorylated in vitro to the extent of 12 mol/mol with GTP at the same sites as can be labelled by the cyclic AMP-independent protein kinase utilizing [gamma-32P]ATP as the phosphoryl donor [15].

Regulatory relationships of MAP2

• Using our cell ELISA protocol, we demonstrate a developmental increase of both cell markers which reflected an increase in the number of opsin-positive cells but an enhanced expression per cell in the case of MAP2 [12].

Other interactions of MAP2

• But while after extended recovery from NaCN lesion protein expression was normalizing (MAP2) or at least still detectable (MAP1A, tau), the consequences of a permanent IM lesion were more severe, since neurons were not able to maintain or even restore their MAP expression [8].
• The cells are immunoreactive with antibodies to MAP2 and neuron specific enolase, two proteins characteristic of neurons [16].
• For standardization of the assay, we employed antibodies against opsin and microtubule-associated protein (MAP2) which label distinct retinal cell classes [12].
• Using fluorescence immunocytochemistry, we investigated whether Cx43 staining was concentrated in specific cellular compartments at H1 by applying well-known markers for astrocytes (glial fibrillary acidic protein; GFAP), oligodendrocytes (antimyelin), neurons (microtubule-associated protein 2), and synaptic terminals (synaptotagmin) [17].
• The data suggest that a tau repetitive sequence (also found in MAP-2 and MAP-4) containing a common tubulin binding motif may constitute a functional domain on tau for the dynamics of the interconnections between actin filaments and microtubules [18].

Analytical, diagnostic and therapeutic context of MAP2

• The abundance of MAP1, MAP2, and tau was evaluated by immunoblotting and, for MAP2, by immunohistochemistry also [8].
• After the following MAP2 degradation phase--i.e. after eight days in vitro--the MAP2 contents were determined by western blotting [1].
• The question if the higher MAP2 levels are due to an alleviation of proteolysis, to a higher synthesis rate or both is addressed in the current investigation: Monitoring the MAP2 content of primary neuronal cell cultures over a period of eight days revealed MAP2 to reach a peak level on day six in vitro followed by a degradation phase [1].
• 2) Cooperativity is indicated independently by a highly clustered or patchy distribution of MAP2 on MTs as revealed by immunoelectron microscopy [10].
• Finally, these studies were extended to cultured primary rat neurons, where double immunofluorescence labeling with anti-LR7/8B and anti-microtubuli-associated protein 2 (MAP2) confirmed the somatodendritic expression of the receptor [19].

References