Accumulation of aberrant proteins in the endoplasmic reticulum (ER) triggers the unfolded protein response pathway that helps the cell to survive under these stress conditions. Herp is a mammalian ubiquitin domain protein, which is strongly induced by the unfolded protein response. It is involved in ER-associated protein degradation (ERAD) and interacts directly with the ubiquitin ligase Hrd1, ...

Wallace DP, Quante MT, Reif GA, Nivens E, Ahmed F, Hempson SJ, Blanco G, Yamaguchi T. Periostin induces proliferation of human autosomal dominant polycystic kidney cells through Vintegrin receptor. Am J Physiol Renal Physiol 295: F1463–F1471, 2008. First published August 27, 2008; doi:10.1152/ajprenal.90266.2008.— Progressive renal enlargement due to the growth of innumerable fluid-filled cysts...

Calcium is essential for normal epidermal differentiation. Data from Northern and nuclear run-on analysis indicate that involucrin gene transcription is induced by 1.2 mM extracellular calcium. A 3.7 Kbp fragment of the involucrin gene, which contains 2.5 Kbp of upstream region, the transcription start site, and the first intron, was sub-cloned into the pGL3-basic luciferase reporter vector and...

Epidermal stem cells (SC) are believed to be resistant to environmental damage for the purpose of self renewal. Most promising SC markers include integrin α6 and p63. The aim of our study was to determine whether the integrin α6+p63+ cell fraction representative of the epidermal progenitor or SC is increased after ultraviolet B (UVB) irradiation and to clarify the hypothesis that epidermal SC a...

The Golgi complex has been implicated as a possible component of endoplasmic reticulum (ER) glycoprotein quality control, although the elucidation of its exact role is lacking. ERManI, a putative ER resident mannosidase, plays a rate-limiting role in generating a signal that targets misfolded N-linked glycoproteins for ER-associated degradation (ERAD). Herein we demonstrate that the endogenous ...

The mammalian translocon-associated protein (TRAP) complex comprises four transmembrane protein subunits in the endoplasmic reticulum. The complex associates with the Sec61 translocon, although its function in vivo remains unknown. Here, we show the involvement of the TRAP complex in endoplasmic reticulum-associated degradation (ERAD). All four subunits are induced simultaneously by endoplasmic...