microtubule-associated protein 1S (MAP 1S, BPY2-interacting protein 1, microtubule-associated protein 8, variable charge Y chromosome 2-interacting protein 1, VCY2-interacting protein 1, protein VCY2IP-1, [contains: MAP1S heavy chain; MAP1S light chain] MAP1S, BPY2IP1, C19orf5, MAP8, VCY2IP1)

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Function

microtubule-associated protein
mediates aggregation of mitochondria resulting in cell death & genomic destruction (MAGD)
plays a role in anchoring the microtubule-organizing center to the centrosomes
binds to DNA
plays a role in apoptosis
involved in the formation of microtubule bundles
interacts with microtubules & actin
both MAP1S heavy & light chains interact with microtubules
MAP1S light chain interacts with actin
interacts with ESR1, LRPPRC, RASSF1 isoform A & isoform C, microtubules & VCY2

heterodimer of a heavy & a light chain.
N-terminus of the heavy chain associates with the C-terminus of the light chain to form the heterodimer
its C-terminal part of the heavy chain interacts with ESR1
belongs to the MAP1 family

nucleus, cytoplasm, cytosol, cytoplasm, cytoskeleton
detected in filopodia-like protrusions & synapses (putative)
detected in perinuclear punctate network corresponding to mitochondrial aggregates & in the nucleus in cells exhibiting apoptosis
associated specifically with microtubules stabilized by paclitaxel & colocalizes with RASSF1 isoform A
in interphase cells, shows a diffuse cytoplasmic staining with partial localization to the microtubules
during the different stages of mitosis detected at the spindle microtubules

expressed in neurons (at protein level)
expressed in spermatocytes, spermatids & spermatozoa
expressed in the cerebral cortex
highly expressed in testis
expressed in the brain, colon, heart, kidney, liver, lung, placenta, small intestine, spleen & stomach > muscle

depletion of MAP1S by RNAi causes mitotic abnormalities that consist of failure to form a stable metaphase plate, premature sister chromatid separation, lagging chromosomes, & multipolar spindles