Makita R et al. - Taz-null/lacZ knock-in mutant homozygotes demonstrated renal cyst formation as early as embryonic day 15.5 with dilatation of Bowman's capsules and proximal tubules, followed by pelvic dilatation and hydronephrosis. After birth, only one-fifth of TAZ-deficient homozygotes grew to adulthood and demonstrated multicystic kidneys with severe urinary concentrating defects and polyuria. Furthermore, adult TAZ-deficient homozygotes exhibited diffuse emphysematous changes in the lung. Thus, TAZ is essential for developmental mechanisms involved in kidney and lung organogenesis, whose disturbance may lead to the pathogenesis of common human diseases