Molecular Target Synopsis
Domains and Structures
Drugs and Clinical Candidates
Ligand Efficiency Plot
Family Cladogram
Interaction Network
Gene Expression
Gene Copy Number Variation
Germline Genetics

MYLK (Q15746) - Overview - Molecular Target Synopsis


MYLK, Myosin light chain kinase, smooth muscle
Enzyme Classification
UniProt Q15746


Calcium/calmodulin-dependent myosin light chain kinase implicated in smooth muscle contraction via phosphorylation of myosin light chains (MLC). Also regulates actin-myosin interaction through a non-kinase activity. Phosphorylates PTK2B/PYK2 and myosin light-chains. Involved in the inflammatory response (e.g. apoptosis, vascular permeability, leukocyte diapedesis), cell motility and morphology, airway hyperreactivity and other activities relevant to asthma. Required for tonic airway smooth muscle contraction that is necessary for physiological and asthmatic airway resistance. Necessary for gastrointestinal motility. Implicated in the regulation of endothelial as well as vascular permeability, probably via the regulation of cytoskeletal rearrangements. In the nervous system it has been shown to control the growth initiation of astrocytic processes in culture and to participate in transmitter release at synapses formed between cultured sympathetic ganglion cells. Critical participant in signaling sequences that result in fibroblast apoptosis. Plays a role in the regulation of epithelial cell survival. Required for epithelial wound healing, especially during actomyosin ring contraction during purse-string wound closure. Mediates RhoA-dependent membrane blebbing. Triggers TRPC5 channel activity in a calcium-dependent signaling, by inducing its subcellular localization at the plasma membrane. Promotes cell migration (including tumor cells) and tumor metastasis. PTK2B/PYK2 activation by phosphorylation mediates ITGB2 activation and is thus essential to trigger neutrophil transmigration during acute lung injury (ALI). May regulate optic nerve head astrocyte migration. Probably involved in mitotic cytoskeletal regulation. Regulates tight junction probably by modulating ZO-1 exchange in the perijunctional actomyosin ring. Mediates burn-induced microvascular barrier injury; triggers endothelial contraction in the development of microvascular hyperpermeability by phosphorylating MLC. Essential for intestinal barrier dysfunction. Mediates Giardia spp.-mediated reduced epithelial barrier function during giardiasis intestinal infection via reorganization of cytoskeletal F-actin and tight junctional ZO-1. Necessary for hypotonicity-induced Ca(2+) entry and subsequent activation of volume-sensitive organic osmolyte/anion channels (VSOAC) in cervical cancer cells. Responsible for high proliferative ability of breast cancer cells through anti-apoptosis. All isoforms including Telokin bind calmodulin. Interacts with SVIL (By similarity). Interacts with CTTN; this interaction is reduced during thrombin-induced endothelial cell (EC) contraction but is promoted by the barrier-protective agonist sphingosine 1-phosphate (S1P) within lamellipodia. A complex made of ABL1, CTTN and MYLK regulates cortical actin-based cytoskeletal rearrangement critical to sphingosine 1-phosphate (S1P)-mediated endothelial cell (EC) barrier enhancement. Binds to NAA10/ARD1 and PTK2B/PYK2.

Inspect Structure
See all 3D Structures for MYLK

Isoforms / Transcripts (Protein Coding)

Sub-cellular localization

UniProt: MYLK is active in the following subcellular-locations: cell projection, cleavage furrow, cytoplasm, cytoskeleton, lamellipodium, stress fiber.
GO terms: MYLK is active in the following subcellular-locations: actin cytoskeleton, cleavage furrow, cytoplasm, cytosol, lamellipodium, plasma membrane, stress fiber.

GO terms

Gene Copy Number Variation

In COSMIC - Cell Lines Project MYLK has gain in 2 cell-lines, loss in 2 cell-lines and no signal in 1000 cell-lines. (see details)

Gene Expression

In NCI60, the highest expressing cell lines are: UO_31, SF_295, SNB_75

In Array Express (RNA-seq of 675 commonly used human cancer cell lines), the highest expressing cell lines are: Hs 255.T, Hs 675.T, M059J

In Array Express (RNA-seq of long poly adenylated RNA and long non poly adenylated RNA from ENCODE cell lines), the highest expressing cell lines are: SK-N-SH, NHLF, BJ

(see details)

RNA Interference

MYLK was reported in the following RNAI studies:

Cell - Large Scale Profiling of Kinase Dependencies in Cancer Cell Lines, the highest RNAi cell lines are: JIMT1, HCC202. (see details)

3D Structures

For MYLK there are:
6 structures (8 chains) solved
0 are solved in complex with at least one small molecule ligand

(see details)
Molecular Target 3D Synopsis

Screening and Chemistry

MYLK has been screened with 485 compounds (822 bioactivities), 34 compounds have bioactivities that show binding affinity of <= 500nM (45 bioactivities). (see details)