Microtubule-associated proteins 1A/1B light chain 3A is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

that in humans is encoded by the ''MAP1LC3A''

gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...

. Two transcript variants encoding different isoforms have been found for this gene.

Function

MAP1A Microtubule-associated protein 1A is a protein that in humans is encoded by the ''MAP1A'' gene. Function This gene encodes a protein that belongs to the microtubule-associated protein family. The proteins of this family are thought to be involv ...

and

MAP1B Microtubule-associated protein 1B is a protein that in humans is encoded by the ''MAP1B'' gene. Function This gene encodes a protein that belongs to the microtubule-associated protein family. The proteins of this family are thought to be invol ...

are microtubule-associated proteins which mediate the physical interactions between microtubules and components of the

cytoskeleton The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is com ...

and

each consist of a heavy chain subunit and multiple light chain subunits. The protein encoded by this gene is one of the light chain subunits and can associate with either MAP1A or MAP1B. MAPLC3A is one of the mammalian homologues of yeast ATG8, an important marker and effector of autophagy.

Regulation

MAP1LC3A is regulated by several

post-translational modification Post-translational modification (PTM) is the covalent and generally enzymatic modification of proteins following protein biosynthesis. This process occurs in the endoplasmic reticulum and the golgi apparatus. Proteins are synthesized by ribos ...

s. These include covalent linkage of the C-terminus to

phosphatidylethanolamine Phosphatidylethanolamine (PE) is a class of phospholipids found in biological membranes. They are synthesized by the addition of cytidine diphosphate- ethanolamine to diglycerides, releasing cytidine monophosphate. ''S''-Adenosyl methionine can ...

in autophagic membranes, and phosphorylation by

protein kinase A In cell biology, protein kinase A (PKA) is a family of enzymes whose activity is dependent on cellular levels of cyclic AMP (cAMP). PKA is also known as cAMP-dependent protein kinase (). PKA has several functions in the cell, including regulatio ...

, which downregulates its autophagy functions. Noncovalent interactions are important for its cargo targeting functions in selective autophagy. For example, it has been shown to

interact Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...

with

sequestosome 1 Sequestosome-1 is a protein that in humans is encoded by the ''SQSTM1'' gene. Also known as the ubiquitin-binding protein p62, it is an autophagosome cargo protein that targets other proteins that bind to it for selective autophagy. By interacti ...

Function

Regulation

References

Further reading