The fission yeast Schizosaccharomyces pombe undergoes "closed" mitosis in which the nuclear envelope (NE) stays intact throughout chromosome segregation. Here we show that Tts1, the fission yeast TMEM33 protein that was previously implicated in organizing the peripheral endoplasmic reticulum (ER), also functions in remodeling the NE during mitosis. Tts1 promotes insertion of spindle pole bodies...

Embedded in the nuclear envelope, nuclear pore complexes (NPCs) not only regulate nuclear transport but also interface with transcriptionally active euchromatin, largely silenced heterochromatin, as well as the boundaries between these regions. It is unclear what functional role NPCs play in establishing or maintaining these distinct chromatin domains. We report that the yeast NPC protein Nup17...

Nuclear localized inositol phospholipids and inositol phosphates are important for regulating many essential processes in animal and yeast cells such as DNA replication, recombination, RNA processing, mRNA export and cell cycle progression. An overview of the current literature indicates the presence of a plant nuclear phosphoinositide (PI) pathway. Inositol phospholipids, inositol phosphates, ...

The activity of nuclear receptors is modulated by numerous coregulatory factors. Corepressors can either mediate the ability of nuclear receptors to repress transcription, or can inhibit transactivation by nuclear receptors. As we learn more about the mechanisms of transcriptional repression, the importance of repression by nuclear receptors in development and disease has become clear. The prot...

Molecular Biology of the Cell REFERENCES Brody Y, Neufeld N, Bieberstein N, Causse SZ, Bohnlein EM, Neugebauer KM, Darzacq X, Shav-Tal Y (2011). The in vivo kinetics of RNA polymerase II elongation during co-transcriptional splicing. PLoS Biol 9, e1000573. Noble KN, Tran EJ, Alcazar-Roman AR, Hodge CA, Cole CN, Wente SR (2011). The Dbp5 cycle at the nuclear pore complex during mRNA export II: n...

Aortic valve stenosis (AS) is a major health problem. Extensive myocardial remodeling increases operative risk and might lead to incomplete reverse with persistent symptoms after aortic replacement (AVR); this makes the optimal timing of AVR clinical challenge. The pathogenesis behind unclear. Central among signaling pathways in heart pro-hypertrophic Ca 2+ -activated calcineurin its downstream...

Members of the actin family have well-characterized cytoskeletal functions, but actin and actin-related proteins (ARPs) have also been implicated in nuclear activities. Previous analyses of the actin family have identified four conserved subfamilies, but many actin-related proteins (ARPs) do not fall into these groups. A new systematic phylogenetic analysis reveals that at least eight ARP subfa...

The hormonally active form of vitamin D, 1,25(OH)2D3, is involved in many biological functions throughout the body, such as regulation of calcium and phosphate homeostasis, bone remodeling and controlling cell proliferation and differentiation. Vitamin D receptor (VDR), a member of the nuclear hormone receptor (NHR) super family, mediates those genomic actions of 1,25 (OH)2D3 by actively repres...