Aquaporin 3, a glycerol and water transporter, is regulated by p73 of the p53 family

p73, a member of the p53 family, has been shown to exhibit similar biochemi cal activities to that of p53. However, in contrast to p53, p73 is rarely m utated in human tumors and p73 mutant mice develop neurological, pheromonal , and inflammatory defects, but not spontaneous tumors. Furthermore, p73 mu tant mice are deficient in the physiological control of cerebral spinal flu id. To determine what mediates these p73 activities, cDNA subtraction assay was performed to identify cellular genes that are regulated by p73. We fou nd that aquaporin 3 (AQP3), a glycerol and mater transporter, is regulated by p73. In addition, we identified a potential p53 response element in the promoter of the AQP3 gene, which is responsive to p73. This suggests that A QP3 may mediate the activity of p73 in maintaining cerebral spinal fluid dy namics. (C) 2001 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.