Quantitative transcriptional profiling of ATDC5 mouse progenitor cells during chondrogenesis
DIFFERENTIATION
Authors: Chen, L; Fink, T; Zhang, XY; Ebbesen, P; Zachar, V
Abstract
During the differentiation of a mouse chondroprogenitor cell line, ATDC5, an analysis of the transcription cartilage-related genes was carried out using real-time RT-PCR in a semiquantitative fashion. A total number of 104 genes both previously linked to chondrogenesis and hitherto not associated with the development of cartilage were analyzed. Parametric statistics, and unsupervised hierarchical and K-medians clustering approaches were used to analyze the gene expression during the sequential processes of proliferation, condensation, differentiation, maturation, and hypertrophic conversion of ATDC5 cells. The obtained data provided a robust determination of expression patterns that make possible an accurate assessment of the molecular events along the chondrogenic differentiation pathway. In addition, time-course expression profiles were described for eight highly regulated genes that have not been associated with chondrogenesis as yet. These included Cryab, Rcor2, Hig1, Bnip3, Mst4, Calml4, Gng2, and Islr.
Establishment of a proteome profile and identification of molecular markers for mouse spermatogonial stem cells
JOURNAL OF CELLULAR AND MOLECULAR MEDICINE
Authors: Zhou, Quan; Guo, Yueshuai; Zheng, Bo; Shao, Binbin; Jiang, Min; Wang, Gaigai; Zhou, Tao; Wang, Lei; Zhou, Zuomin; Guo, Xuejiang; Huang, Xiaoyan
Abstract
Spermatogonial stem cells (SSCs) are undifferentiated cells that are required to maintain spermatogenesis throughout the reproductive life of mammals. Although SSC transplantation and culture provide a powerful tool to identify the mechanisms regulating SSC function, the precise signalling mechanisms governing SSC self-renewal and specific surface markers for purifying SSCs remain to be clearly determined. In the present study, we established a steady SSC culture according to the method described by Shinohara's lab. Fertile progeny was produced after transplantation of cultured SSCs into infertile mouse testis, and the red fluorescence exhibited by the culture cell membranes was stably and continuously transmitted to the offspring. Next, via advanced mass spectrometry and an optimized proteomics platform, we constructed the proteome profile, with 682 proteins expressed in SSCs. Furthermore bioinformatics analysis showed that the list contained several known molecules that are regulated in SSCs. Several nucleoproteins and membrane proteins were chosen for further exploration using immunofluorescence and RT-PCR. The results showed that SALL1, EZH2, and RCOR2 are possibly involved in the self-renewal mechanism of SSCs. Furthermore, the results of tissue-specific expression analysis showed that Gpat2 and Pld6 were uniquely and highly expressed in mouse testes and cultured SSCs. The cellular localization of PLD6 was further explored and the results showed it was primarily expressed in the spermatogonial membrane of mouse testes and cultured SSCs. The proteins identified in this study form the basis for further exploring the molecular mechanism of self-renewal in SSCs and for identifying specific surface markers of SSCs.