Nagasaki University School of MEDICAL SCIENCES

Research Areas

Department of
Histology and Developmental Anatomy

Professor Takehiko Koji

This department teaches a course and practical training on human development and histology to educate students about observation of histological tissue specimen.
Our research purpose is to elucidate the molecular mechanisms of cell functional and structural differentiation using the methods of molecular histochemistry and immunohistochemistry with super-resolution microscopy and electron microscopy. Two new methods, southwestern histochemistry and histo endonuclease-linked detection of methylated DNA sites (HELMET) had been established in this department. Southwestern histochemistry is a molecular histochemical tool for analysis of expression of transcription factors and HELMET was designed to detect methylation sites of DNA with specific sequences in a tissue section. With these methods, we analyze the roles of epigenetic factors, such as DNA methylation, histone modification and microRNAs in the regulation of cell kinetics in testes, intestinal epithelium as self-renewing organs and liver as non-self-renewing organ of in vivo model animals. Immunohistochemistry and HELMET revealed the dynamic changes of DNA methylation at CCGG sites and histone acetylation during the process of spermatogenesis and inhibition of enzymes for the regulation of DNA methylation and histone acetylation impaired mouse spermatogenesis at specific stages.