Lack of iron-related phenotype in Sp6 intestinal knockout mice.

Based on a microarray study, which demonstrated the upregulation of Sp6 transcriptional factor in iron deficient rat duodenum, we reasoned that SP6 could regulate iron absorption by controlling the expression of iron absorption genes (Collins,2006). For that, we generated Sp6 specific intestinal knockout mice. Our data suggest a lack of transcriptional upregulation of Sp6 in mice in conditions where iron absorption is promoted (phlebotomy, iron deficiency, hpx mouse), and an absence of iron-related phenotype in Sp6 intestinal knockout model. We propose that other Sp6 orthologues may be involved in the genetic response to increase iron absorption, possibly in co-operation with hypoxia inducible factor 2 alpha (HIF-2α)-a newly discovered regulator of iron absorption.