Mucolipin-3 also known as TRPML3 (transient receptor potential cation channel, mucolipin subfamily, member 3) is a
protein that in humans is encoded by the ''MCOLN3''
gene.
It is a member of the small family of the
TRPML channels, a subgroup of the large protein family of
TRP ion channels.
Gene
In human, the ''MCOLN3'' gene resides on the short arm of
chromosome 1 at 1p22.3. The gene is split in 12
exons
An exon is any part of a gene that will form a part of the final mature RNA produced by that gene after introns have been removed by RNA splicing. The term ''exon'' refers to both the DNA sequence within a gene and to the corresponding sequence ...
, which entail the open reading frame of 1659 nucleotides. The encoded protein, TRPML3, has 553 amino acid with a predicted molecular weight of ≈64
kDa. Computational analyses of the secondary structure predict the presence of six
transmembrane domains, an ion transport motif (PF00520) and a
transient receptor potential motif (PS50272).
In the mouse, ''Mcoln3'', is located on the distal end of
chromosome 3 at cytogenetic band qH2. Human and mouse TRPML3 proteins share 91% sequence identity.
All vertebrate species, for which a genomic sequence is available, harbor the ''MCOLN3'' gene. Homologs of ''MCOLN3'' are also present in the genome of insects (''
Drosophila melanogaster''), nematodes (''
Caenorhabditis elegans
''Caenorhabditis elegans'' () is a free-living transparent nematode about 1 mm in length that lives in temperate soil environments. It is the type species of its genus. The name is a blend of the Greek ''caeno-'' (recent), ''rhabditis'' (ro ...
''), sea urchin (''
Strongylocentrotus purpuratus'') and lower organisms including Hydra and Dictyostelium.
Expression
Function
TRPML3 is an inwardly-rectifying
cation
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...
channel.
Genetics
Phenotypes
Mutations of the MCOLN3 gene in mice result in auditory
hair cell death and
deafness.
Ligands
; Agonists (channel activators)
*
ML-SA1 (non selective vs
TRPML1)
*
SN-2 (highly selective for TRPML3)
See also
* transient receptor potential cation channel, mucolipin subfamily, member 1 (
MCOLN1)
* transient receptor potential cation channel, mucolipin subfamily, member 2 (
MCOLN2)
References
Further reading
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External links
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