In the process of morphogenesis primordia of lateral organs, like leaves or flowers, are formed at the shoot apical meristem (SAM). In order to maintain the ability to organ formation, the SAM itself has to be self-perpetuated, i.e. its general shape and size have to be maintained, despite the fact that portions of SAM periphery are continuously used up for lateral organ formation. Thus growth ...

In mammals, aldosterone is produced in the zona glomerulosa (zG), the outermost layer of the adrenal cortex, whereas glucocorticoids are produced in adjacent zona fasciculata (zF). However, the cellular mechanisms controlling the zonal development and the differential hormone production (i.e. functional zonation) are poorly understood. To explore the mechanisms, we defined zone-specific transcr...

Heterogeneous zonation of hepatic protein expression over the liver lobule has been recognized by using several analytical techniques, including microdissection, selective cell isolation, immunohistochemistry and hybridization of mRNA in situ. We previously employed the technique of dual-digitonin-pulse perfusion for the highly selective collection and analysis of periportal and perivenous solu...

The theoretical basis of the use of the multiple indicator dilution technique to account for the heterogeneous distribution (or zonation) of enzymes in the liver was explored. The microcirculation was assumed to consist of identical capillaries perfused in parallel, with enzymatic activities for drug metabolism being distributed uniformly over the upstream half (periportal or pp) or the downstr...