WD repeat domain phosphoinositide-interacting protein 4 (WIPI-4) 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, respo ...

that in humans is encoded by the ''WDR45''

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 ba ...

. Mutations in this gene cause a distinct form of ''

Neurodegeneration with brain iron accumulation Neurodegeneration with brain iron accumulation is a heterogenous group of inherited neurodegenerative diseases, still under research, in which iron accumulates in the basal ganglia, either resulting in progressive dystonia, Parkinsonism, spastici ...

'' (NBIA) called Beta-propeller protein-associated neurodegeneration (BPAN).

Function

WIPI-4 is a member of the

WD repeat The WD40 repeat (also known as the WD or beta-transducin repeat) is a short structural motif of approximately 40 amino acids, often terminating in a tryptophan-aspartic acid (W-D) dipeptide. Protein tandem repeats, Tandem copies of these repeats ...

protein family. WD repeats are minimally conserved regions of approximately 40 amino acids typically bracketed by gly-his and trp-asp (GH-WD), which may facilitate formation of heterotrimeric or multiprotein complexes. Members of this family are involved in a variety of cellular processes, including

cell cycle The cell cycle, or cell-division cycle, is the series of events that take place in a cell that cause it to divide into two daughter cells. These events include the duplication of its DNA (DNA replication) and some of its organelles, and subs ...

progression,

signal transduction Signal transduction is the process by which a chemical or physical signal is transmitted through a cell as a series of molecular events, most commonly protein phosphorylation catalyzed by protein kinases, which ultimately results in a cellula ...

apoptosis Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes (morphology) and death. These changes incl ...

, and gene regulation. This gene WDR45 has a pseudogene at chromosome 4q31.3. Multiple alternatively spliced transcript variants encoding distinct isoforms have been found for this gene, but the biological validity and full-length nature of some variants have not been determined.

Role in disease

De novo loss of function mutations in ''WDR45'' were identified by exome sequencing in 20 patients with progressive neurodegeneration and evidence of iron on brain MRI scans. The mutations cause an X-linked dominant form of NBIA now called Beta-propeller protein-associated neurodegeneration (BPAN). A name for the disease before the gene was identified was called static encephalopathy of childhood with neurodegeneration in adulthood (SENDA), though this term is no longer used. There are no current treatments for BPAN, though medications and therapies can be used to treat symptoms.

Function

Role in disease

See also

References

Further reading