Human PRKCZ ELISA Matched Antibody Pair

Specification of the trophectoderm (TE) and inner cell mass (ICM) lineages in the mouse blastocyst correlates with cell position, as TE derives from outer cells whereas ICM from inner cells. Differences in position are reflected by cell polarization and Hippo signaling. Only in outer cells, the apical-basal cell polarity is established, and Hippo signaling is inhibited in such a manner that LATS1 and 2 (LATS1/2) kinases are prevented from phosphorylating YAP, a key transcriptional co-activator of the TE-specifying gene Cdx2. However, the molecular mechanisms that regulate these events are not fully understood. Here, we showed that inhibition of RHO-ROCK signaling enhances ICM and suppresses TE characteristics through activation of Hippo signaling and disruption of apical-basal polarity. Embryos treated with ROCK inhibitor Y-27632 exhibited elevated expression of ICM marker NANOG and reduced expression of CDX2 at the blastocyst stage. Y-27632-treated embryos failed to accumulate YAP in the nucleus, although it was rescued by concomitant inhibition of LATS1/2. Segregation between apical and basal polarity regulators, namely PARD6B, PRKCZ, SCRIB, and LLGL1, was dampened by Y-27632 treatment, whereas some of the polarization events at the late 8-cell stage such as compaction and apical localization of p-ERM and tyrosinated tubulin occurred normally. Similar abnormalities of Hippo signaling and apical-basal polarization were also observed in embryos that were treated with RHO GTPases inhibitor. These results suggest that RHO-ROCK signaling plays an essential role in regulating Hippo signaling and cell polarization to enable proper specification of the ICM and TE lineages. (C) 2014 Elsevier Inc. All rights reserved.

Background Protein kinase C iota (PKC iota) and protein kinase C zeta (PKC zeta) are two atypical protein kinase (aPKC) enzymes that contribute to cell proliferation and cancer development. The Hippo/YAP pathway is commonly disrupted and upregulated in cancers. Herein, the expression patterns and clinical relevance of PKC iota and PKC zeta are evaluated in relation to YAP, a downstream effector of Hippo, in lung adenocarcinoma (LAC). The protein and mRNA expression levels of PKC iota, PKC zeta, YAP, and their phosphorylated forms, namely p-PKC iota, p-PKC zeta and p-YAP, are evaluated in relation to clinicopathological factors, including patient survival. Methods A total of 200 primary LAC tissue samples were examined by immunohistochemistry for PKC iota, p-PKC iota, PKC zeta, p-PKC zeta, YAP, and p-YAP protein expression. Sixty pairs of LAC and non-neoplastic lung tissue samples were assessed for PRKCI, PRKCZ, and YAP mRNA levels. PKC iota, p-PKC iota, PKC zeta, and p-PKC zeta protein expression were evaluated by Western blot analysis in the PC9 and PC9/GR LAC cell lines with YAP modulation. Results LAC demonstrated cytoplasmic PKC iota, p-PKC iota, PKC zeta, and p-PKC zeta immunostaining patterns. Positive aPKC protein expressions were related with poor patient survival. Especially, increased p-PKC iota protein expression was significantly correlated with higher pathological stage and shortened overall survival. YAP overexpression contributes phosphorylation of PKC iota and PKC zeta protein expression in the LAC cell line. Conclusions PKC iota and PKC zeta are related to YAP in LAC. PKC iota and PKC zeta play distinct roles in LAC; specifically, p-PKC iota overexpression is suggested to underlie factors that indicate a poor prognosis.