Comparison of PLZF Gene Expression between Pluripotent Stem Cells and Testicular Germ Cells

Spermatogonial stem cells (SSCs), as unipotent stem cells, are responsible for the production of sperm throughout the male's life. Zinc finger and BTB domain containing 16 (ZBTB16/PLZF) genes provide various functions in the cell development, signaling pathway, growth regulatory and differentiation. Here, we aimed to investigate expression of the PLZF germ cell gene marker in testis, SSCs, pluripotent embryonic stem cells (ES cells) and ES-like cells of mouse testis.

In this experimental study, we examined the expression of the PLZF germ cell marker in the testis section and testicular cell culture of neonate and adult mice by immunohistochemistry (IMH), immunocytochemistry (ICC) and Fluidigm Real-Time polymerase chain reaction (PCR).

IMH data indicated that the PLZF protein was localized in the neonate testis cells of the tubules center as well as the basal compartment of adult testis seminiferous tubules. Counting PLZF IMH-positive cells in the sections of seminiferous tubules of adult and neonate testis revealed significant expression of positive cells in adult testis compared to the neonate (P<0.05). Under in vitro conditions, isolated SSC colonies were strongly ICC-positive for the PLZF germ cell marker, while ES cells and ES-like cells were negative for PLZF. Fluidigm Real-Time-PCR analysis demonstrated a significant expression of the PLZF germ cell gene in the neonate and adult SSCs, compared to ES cells and ES-like cells (P<0.05).

These results indicate that PLZF is a specific transcription factor of testicular germ cell proliferation, but it is downregulated in pluripotent germ cells. This can be supportive for the analysis of germ cells development both in vitro and in vivo.