Inducible dominant negative ErbB2 rat spermatogonial line for generation of transgenic rat model and dissecting ERBB2 tyrosine kinase mediated pathways

Abstract

Summary. Aim: The ERBB2 receptors tyrosine kinase, also known as HER2/Neu, play an essential role in early organism development and modulation of cell behavior in varieties of tissue in an adult organism. Our aim was the generation of transgenic rat spermatogonial line capable of inducible expression of a dominant negative form of the ERBB2 protein in vitro and the transgenic rat as an animal model for dissection of the ERBB2 mediated signaling in vitro and in vivo. Materials and Methods: Donor derived rat spermatogonial stem cells that express green fluorescence protein and inducible ERT2CreERT2 recombinase were modified with Sleeping Beauty transposon-based vector that express truncated kinase deficient form of the ERBB2 receptor upon Cre mediated recombination. Clonally selected spermatogonial cell lines were extensively tested in vitro. Animals were generated via spermatogonia mediated transgenesis by transplantation of clonal cell line into testes of chemically sterilized recipients. Obtained progeny were tested for inducibility in vivo and served as donors of spermatogonia for downstream analysis. Results: We obtained animals and clonally derived spermatogonial stem cell lines that express an inducible dominant negative form of the ERBB2 protein. Isogenic nature of induced and uninduced cells allows most accurate morphological and molecular comparison of cells affected by the interruption of normal function of the ERBB2 receptor and cellular dynamics in vitro and in vivo. Conclusions: Clonally derived spermatogonial stem cell lines that express an inducible dominant negative form of ErbB2 demonstrated an obvious difference in morphological appearance and growth kinetics of induced cells comparing to uninduced ones. Western blot analysis of induced and uninduced cells revealed significant differences in presence and phosphorylation state of several tested important proteins involved in the ERBB2 mediated signal transduction, such as S6 ribosomal protein; AKT (the serine/threonine kinase also known as protein kinase B); and three protein kinases that participate in the RAS-RAF-MEK-ERK signal transduction cascade PRAS40, MEK, ERK1/2.

Therapeutic Effect of Berberine on Insomnia Rats by ErbB Signaling Pathway

“…Reduced activity of TRN neurons may explain abnormal sleep function [ 45 ]. Erbb2 receptor tyrosine kinase plays a major role in early development and regulation of various cell behaviors [ 46 ]. It has been found that androgen receptor (Ar) in the main circadian clock of suprachiasmatic nucleus regulates the effect of light on male activity [ 47 ].…”