Journal of Cellular Signaling

Original Research Open Access

PAX-Interacting Protein 1 (PTIP) Promotes Apoptosis

Ching-Jung Huang , Hyein Cho , Chuan Li , Kangsan Kim , Danyang Yu , Daechan Park , Y. Jessie Zhang , Haley O. Tucker

PAX-interacting protein 1 (PTIP/PAXIP1) was discovered and initially characterized over three decades ago as a 1,056 amino acid-containing protein with six tandem BReast cancer C-Terminal (BRCT) repeats. PTIP functions broadly to catalyze histone methylation in DNA damage repair and within the hematopoietic lineage, to promote immunoglobulin variable region (variable, diversity, joining [VDJ]) and class switch recombination (CSR).

Original Research Open Access

A Newly Characterized, Two BRCT Domain-Containing Isoform of PAX-Interacting Protein (PTIP) Generated via Frame Shift and Alternative Pre-mRNA Splicing

Ching-Jung Huang , Chuan Li , Danyang Yu , Hyein Cho , Kangsan Kim , Y. Jessie Zhang , Daechan Park , Haley O. Tucker

In an effort to clone polyglutamine-rich factors from activated B lymphocytes of mice, we discovered and describe here a previously uncharacterized isoform of PTIP/PAXIP1. By virtue of a two-nucleotide frameshift followed by alternative pre-mRNA splicing, this shorter isoform of 576 amino acids (termed PTIP576) retained only the two central BRCT domains of previously characterized PTIP and encodes a unique and structurally disordered 50 residue C-terminus.

Review Article Open Access

Pathogenic Pathways and Therapeutic Strategies in Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Kenley M. Preval , Abigail O. Smith , Gregory J. Pazour

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disorder and a major cause of end-stage renal disease. The disorder is primarily caused by pathogenic variants in PKD1 or PKD2, which encode the ciliary proteins polycystin-1 and polycystin-2. Loss of polycystin function disrupts calcium and cAMP signaling within the primary cilium, altering epithelial proliferation and fluid secretion that drive cyst formation and progressive kidney enlargement.

Editorial Open Access

When Cells Speak in Many Languages: The Evolving Story of Cellular Signaling

Vivek K Pandey

The current issue of the Journal of Cellular Signaling brings together a diverse set of studies that collectively broaden our understanding of cellular communication, from canonical biochemical pathways to emergent bioelectric and metabolic signaling systems. This editorial review synthesizes the major findings and conceptual advances presented in Volume 6 Issue 3, highlighting the converging trends that redefine how we view signaling as an integrative, dynamic, and multi-dimensional process.

Review Article Open Access

Ubiquitination of Metabotropic Glutamate Receptors and Associated Synaptic Proteins In Vitro and In Vivo

Li-Min Mao , John Q. Wang

Metabotropic glutamate (mGlu) receptors are a family of G protein-coupled receptors. These receptors are widely distributed in the brain and are critical for the modulation of synaptic transmission and plasticity. Emerging evidence shows that mGlu receptors themselves are subject to a dynamic posttranslational modification involving protein ubiquitination.