Two-pore channel protein TPC1 is a determining factor for the adaptation of proximal tubular phosphate handling.

Aim: Two-pore channels (TPCs) constitute a small family of cation channels expressed in endo-lysosomal compartments. TPCs have been characterized as critical elements controlling Ca -mediated vesicular membrane fusion and thereby regulating endo-lysosomal vesicle trafficking. Exo- and endocytotic trafficking and lysosomal degradation are major mechanisms of adaption of epithelial transport.

Dipeptidyl peptidase-4 cell surface expression marks an abundant adipose stem/progenitor cell population with high stemness in human white adipose tissue.

The capacity of adipose stem/progenitor cells (ASCs) to undergo self-renewal and differentiation is crucial for adipose tissue homoeostasis, regeneration and expansion. However, the heterogeneous ASC populations of the adipose lineage constituting adipose tissue are not precisely known. In the present study, we demonstrate that cell surface expression of dipeptidyl peptidase-4 (DPP4)/cluster of differentiation 26 (CD26) subdivides the DLK1/CD34/CD45/CD31 ASC pool of human white adipose tissues (WATs) into two large populations.

An organoid model derived from human adipose stem/progenitor cells to study adipose tissue physiology.

We established a functional adipose organoid model system for human adipose stem/progenitor cells (ASCs) isolated from white adipose tissue (WAT). ASCs were forced to self-aggregate by a hanging-drop technique. Afterwards, spheroids were transferred into agar-coated cell culture dishes to avoid plastic-adherence and dis-aggregation.

Two-Pore Channels Regulate Expression of Various Receptors and Their Pathway-Related Proteins in Multiple Ways.

Two-pore channels (TPCs) constitute a small family of ion channels within membranes of intracellular acidic compartments, such as endosomes and lysosomes. They were shown to provide transient and locally restricted Ca-currents, likely responsible for fusion and/or fission events of endolysosomal membranes and thereby for intracellular vesicle trafficking. Genetic deletion of TPCs not only affects endocytosis, recycling, and degradation of various surface receptors but also uptake and impact of bacterial protein toxins and entry and intracellular processing of some types of viruses.

Two-pore channels affect EGF receptor signaling by receptor trafficking and expression.

Two-pore channels (TPCs) are key components for regulating Ca current from endosomes and lysosomes to the cytosol. This locally restricted Ca current forms the basis for fusion and fission events between endolysosomal membranes and thereby for intracellular trafficking processes. Here, we study the function of TPC1 and TPC2 for uptake, recycling, and degradation of epidermal growth factor receptor (EGFR) using a set of TPC knockout cells.