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== Ferroportin1 ==

Scl11a3 is the gene that encodes the protein ferroportin1, also known as Fnp1. Fnp1 is known to be expressed in the visceral endoderm, placenta, and intestine of developing embryos where it is the sole transporter of iron, playing an extremely important role in iron absorption. Fnp1 is a transmembrane protein consisting of 571 amino acid residues with a conserved histidine at residue position 32 that when mutated exhibits a lower activity of iron transport. During embryonic development Fnp1 plays an important role in neural tube closure and forebrain patterning. Mouse embyros lacking the Scl40a1 (analog to the Slc11a3 in Homo sapiens) are aborted before gastrulation occurs, proving that the Fnp1 protein encoded by the gene Scl11a3 is absolutely required for normal embryonic development. Fnp1 is expressed in the syncytiotrophoblast cells in the placenta and visceral endoderm of mice at E7.5. Further, several retrospective studies have sited an increased incidence of spina bifida with a low maternal intake of iron. According to a recent study done on several different mutants of the Slc40a1 mouse gene, significant neural tube and patterning defects were suffered including spina bifida, exencephaly, and forebrain truncations among others. With these two findings taken together, there is significant evidence towards iron transport being critical to neural tube closure. Interestingly, Fnp1 is required along the entire anterior-posterior axis for proper closure of the neural tube.

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