Publications by authors named "Seth Stauffer"

ATP-activated P2X3 receptors play a pivotal role in chronic cough, affecting more than 10% of the population. Despite the challenges posed by the highly conserved structure of P2X receptors, efforts to develop selective drugs targeting P2X3 have led to the development of camlipixant, a potent, selective P2X3 antagonist. However, the mechanisms of receptor desensitization, ion permeation, and structural basis of camlipixant binding to P2X3 remain unclear.

View Article and Find Full Text PDF

Purinergic P2X3 receptors form trimeric cation-gated channels, which are activated by extracellular ATP. P2X3 plays a crucial role in chronic cough and affects over 10% of the population. Despite considerable efforts to develop drugs targeting P2X3, the highly conserved structure within the P2X receptor family presents obstacles for achieving selectivity.

View Article and Find Full Text PDF

AMP-activated protein kinase (AMPK), a heterotrimeric serine/threonine kinase and cellular metabolic sensor, has been found to regulate cell cycle checkpoints in cancer cells in response to energetic stress, to harmonize proliferation with energy availability. Despite AMPK's emergent association with the cell cycle, it still has not been fully delineated how AMPK is regulated by upstream signaling pathways during mitosis. We report, for the first time, direct CDK1 phosphorylation of both the catalytic α1 and α2 subunits, as well as the β1 regulatory subunit, of AMPK in mitosis.

View Article and Find Full Text PDF

Zyxin is a member of the focal adhesion complex and plays a critical role in actin filament polymerization and cell motility. Several recent studies showed that Zyxin is a positive regulator of Yki/YAP (Yes-associated protein) signaling. However, little is known about the mechanisms by which Zyxin itself is regulated and how Zyxin affects Hippo-YAP activity.

View Article and Find Full Text PDF

PDZ-binding kinase (PBK) plays a major role in proliferation and in safeguarding mitotic fidelity in cancer cells. Frequently upregulated in many cancers, PBK drives tumorigenesis and metastasis. PBK has been shown to be phosphorylated in mitosis by cyclin-dependent kinase 1 (CDK1)/cyclin B, however, no studies have been done examining PBK mitotic phosphorylation in oncogenesis.

View Article and Find Full Text PDF

The Hippo pathway is an evolutionarily conserved signaling pathway that plays important roles in stem cell biology, tissue homeostasis, and cancer development. Vestigial-like 4 (Vgll4) functions as a transcriptional co-repressor in the Hippo-Yes-associated protein (YAP) pathway. Vgll4 inhibits cell proliferation and tumor growth by competing with YAP for binding to TEA-domain proteins (TEADs).

View Article and Find Full Text PDF

Recent studies identified the adaptor protein Ajuba as a positive regulator of Yes-associated protein (YAP) oncogenic activity through inhibiting large tumor suppressor (Lats1/2) core kinases of the Hippo pathway, a signaling pathway that plays important roles in cancer. In this study, we define a novel mechanism for phospho-regulation of Ajuba in mitosis and its biological significance in cancer. We found that Ajuba is phosphorylated in vitro and in vivo by cyclin-dependent kinase 1 (CDK1) at Ser(119) and Ser(175) during the G2/M phase of the cell cycle.

View Article and Find Full Text PDF

KIBRA is a regulator of the Hippo-yes-associated protein (YAP) pathway, which plays a critical role in tumorigenesis. In the present study, we show that KIBRA is a positive regulator in prostate cancer cell proliferation and motility. We found that KIBRA is transcriptionally upregulated in androgen-insensitive LNCaPC4-2 and LNCaP-C81 cells compared to parental androgen-sensitive LNCaP cells.

View Article and Find Full Text PDF

The transcriptional co-activator with PDZ-binding motif (TAZ) is a downstream effector of the Hippo tumor suppressor pathway, which plays important roles in cancer and stem cell biology. Hippo signaling inactivates TAZ through phosphorylation (mainly at S89). In the current study, we define a new layer of regulation of TAZ activity that is critical for its oncogenic function.

View Article and Find Full Text PDF

Yes-associated protein (YAP) is an effector of the Hippo tumor suppressor pathway. The functional significance of YAP in prostate cancer has remained elusive. In this study, we first show that enhanced expression of YAP is able to transform immortalized prostate epithelial cells and promote migration and invasion in both immortalized and cancerous prostate cells.

View Article and Find Full Text PDF