- Peptide (C)EKVTTIMEMASKMKD, corresponding to amino acid residues 242-256 of human magnesium transporter NIPA4 (Accession Q0D2K0). 2nd extracellular loop.
- Western blot analysis of human acute monocytic leukemia cell line THP-1 (lanes 1 and 2), mouse B cell lymphoma cell line WEHI-231 (lanes 3 and 4), rat brain membranes (lanes 5 and 7) and mouse brain membranes (lanes 6 and 8):1,3,5,7. Anti-NIPAL4 (extracellular) Antibody (#ANT-144), (1:400).
2,4,6,8. Anti-NIPAL4 (extracellular) Antibody, preincubated with NIPAL4 (extracellular) Blocking Peptide (#BLP-NT144).
- Cell surface detection of Magnesium transporter NIPA4 in THP-1 (human acute monocytic leukemia cell line) living cells:___ Unstained cells.
___ Cells stained with Anti-NIPAL4 (extracellular) Antibody (#ANT-144), (5 µg/5x105 cells).
- Quamme, G.A. (2010) Am. J. Physiol. Cell Physiol. 298, C407.
The NIPA family is currently comprised of 4 members- NIPA1-4. These members have a molecular similarity of 40%. NIPA proteins are integral membrane proteins which function as Mg2+ transporters.
The NIPA4 gene in mice is located on chromosome 11B1.1 and the human corresponding gene, hIchthyin is located on chromosome 5q33.3. Both genes share an 85% amino acid similarity. Interestingly, NIPA2-4 show greater common identity in their ancestral invertebrate polypeptides than they do to NIPA1 suggesting different physiological roles. NIPA4 mediates Mg2+ uptake with a Km of 0.36 mM but unlike NIPA2, which is selective for Mg2+, it has been found to transport other cations as well.
Mutations in the hIchthyin gene provide the basis of one form of autosomal-recessive congenital ichthyosis (ARCI). ARCI is a heterogenous group of disorders with abnormal differentiation and desquamation of the epidermis, leading to widespread scaling and erythema of the skin. To this day six homozygous mutations have been found, including one nonsense and five missense mutations, in a large number of consanguineous families presenting with ichthyosis. The function of ichthyin in skin differentiation is not fully understood but it has been suggested that because lipid dysfunctions are involved with the other ARCI disorders ichthyin might perform as a membrane receptor for trioxilins of the hepoxilin pathway.
Although some NIPA proteins have been implicated as candidates for prader-willi syndrome their involvement remains unclear. Currently there is no evidence that NIPA4 is directly involved in the many complexities of the syndrome1.
Species reactivity key:
Alomone Labs is pleased to offer a highly specific antibody directed against an epitope of human magnesium transporter NIPA4. Anti-NIPAL4 (extracellular) Antibody (#ANT-144) can be used in western blot and indirect flow cytometry applications. The antibody recognizes an extracellular epitope and is thus ideal for detecting the transporter in living cells. It has been designed to recognize NIPAL4 from mouse, rat and human samples.