Serine/threonine-protein kinase LMTK2 also known as Lemur tyrosine kinase 2 (LMTK2) is an enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

 that in humans is encoded by the LMTK2 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.

Function

The LMTK2 enzyme belongs to both the protein kinase

Protein kinase

A protein kinase is a kinase enzyme that modifies other proteins by chemically adding phosphate groups to them . Phosphorylation usually results in a functional change of the target protein by changing enzyme activity, cellular location, or association with other proteins...

 and the tyrosine kinase

Tyrosine kinase

A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to a protein in a cell. It functions as an "on" or "off" switch in many cellular functions....

 families. It contains N-terminus transmembrane helices and a long C-terminal cytoplasmic tail with serine/threonine/tyrosine kinase activity. This protein interacts with several other proteins, such as inhibitor-2 (Inh2), protein phosphatase-1 (PP1C

PPP1CA

Serine/threonine-protein phosphatase PP1-alpha catalytic subunit is an enzyme that in humans is encoded by the PPP1CA gene.-Interactions:...

), p35

P35 (gene)

The p35 gene encodes a variable of a cytokine that acts on p and natural killer cells, and has a broad array of biological inhancements. The cytokine is a sulfide-linked heterodimer composed of the 35-kD subunit encoded by this gene, and a 40-kD subunit that is a member of the cytokine receptor...

, and myosin VI

Myosin

Myosins comprise a family of ATP-dependent motor proteins and are best known for their role in muscle contraction and their involvement in a wide range of other eukaryotic motility processes. They are responsible for actin-based motility. The term was originally used to describe a group of similar...

. It phosporylates

Phosphorylation

Phosphorylation is the addition of a phosphate group to a protein or other organic molecule. Phosphorylation activates or deactivates many protein enzymes....

 other proteins, and is itself also phosporylated when interacting with cyclin-dependent kinase 5 (cdk5

Cyclin-dependent kinase 5

Cell division protein kinase 5 is an enzyme that in humans is encoded by the CDK5 gene. The protein encoded by this gene is part of the cyclin-dependent kinase family.-Physiological Role:...

)/p35

P35 (gene)

The p35 gene encodes a variable of a cytokine that acts on p and natural killer cells, and has a broad array of biological inhancements. The cytokine is a sulfide-linked heterodimer composed of the 35-kD subunit encoded by this gene, and a 40-kD subunit that is a member of the cytokine receptor...

 complex. This protein involves in nerve growth factor (NGF

Nerve growth factor

Nerve growth factor is a small secreted protein that is important for the growth, maintenance, and survival of certain target neurons . It also functions as a signaling molecule. It is perhaps the prototypical growth factor, in that it is one of the first to be described...

)-TrkA signalling, and also plays a critical role in endosomal

Endosome

In biology, an endosome is a membrane-bound compartment inside eukaryotic cells. It is a compartment of the endocytic membrane transport pathway from the plasma membrane to the lysosome. Molecules internalized from the plasma membrane can follow this pathway all the way to lysosomes for...

 membrane trafficking

Protein targeting

Protein targeting or protein sorting is the mechanism by which a cell transports proteins to the appropriate positions in the cell or outside of it. Sorting targets can be the inner space of an organelle, any of several interior membranes, the cell's outer membrane, or its exterior via secretion...

. Mouse studies suggested an essential role of this protein in spermatogenesis

Spermatogenesis

Spermatogenesis is the process by which male primary germ cells undergo division, and produce a number of cells termed spermatogonia, from which the primary spermatocytes are derived. Each primary spermatocyte divides into two secondary spermatocytes, and each secondary spermatocyte into two...

.

Interactions

LMTK2 has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with PPP1CA

PPP1CA

Serine/threonine-protein phosphatase PP1-alpha catalytic subunit is an enzyme that in humans is encoded by the PPP1CA gene.-Interactions:...

, Cyclin-dependent kinase 5

Cyclin-dependent kinase 5

Cell division protein kinase 5 is an enzyme that in humans is encoded by the CDK5 gene. The protein encoded by this gene is part of the cyclin-dependent kinase family.-Physiological Role:...

 and PPP1R2

PPP1R2

Protein phosphatase inhibitor 2 is an enzyme that in humans is encoded by the PPP1R2 gene.-Interactions:PPP1R2 has been shown to interact with LMTK2 and PPP1R9B.-Further reading:...

.

Further reading