人類遺伝学と発生学

Recent developments in the field of reprogramming somatic cells to induced pluripotent stem cells (iPSC) has brought the field closer to the exciting possibility of their future clinical application. A number of challenges remain to be addressed before clinical application of reprogrammed stem cells becomes a reality. The main issues are the threat of cancer, control of differentiation to tissue specific stem cells or body organs and the immune response of iPSC-derived cells. The future use of iPSC will require that they are cancer free, do not proliferate and can be contained to the specific injection site for tissue regeneration. This review discusses the recent advances that address these main challenges in the field of cellular reprogramming

Heart is pumping throughout life of animals ever since embryogenesis. The mammalian heart consists of four chambers along with specialized myocardial system for electrical conduction and force production, which guarantees the heart to pump efficiently. miR-1, the cardiac specific mi RNA, is suggested to play essential roles in cardiogenesis and in regulating physiological function of heart. During early stage of cardio genesis, miR-1 promotes cardiac mesoderm induction. In the subsequent morphogenesis, miR-1 controls cell fate of various lineages and the balance between proliferation and differentiation so that cardiac chambers could develop normally. In postnatal life, miR-1 modulates atrioventricular and ventricular conduction at multiple levels and contributes to the formation of organized sarcomere. Advance in the role miR-1 plays in cardiac biological processes have put new perspectives on mechanisms of heart diseases.

E-cadherin is an evolutionary conserved molecule expressing from lower level animal to human. The principal role of E-cadherin is to maintain appropriate cell-cell connectivity at adherensjunction. Besides its role as cell-cell connector protein, E-cadherin is integrally involved in intracellular signaling as well as cytoskeletal remodeling. Proper spaciotemporal regulations as well as relevant specialized functions of E-cadherin are important for maintaining normal embryogenesis, cellular morphology and physiological function. However, defects in the expression and function of this gene products could become curses since numerous genetic and developmental studies have identified the critical role of this gene in path physiological conditions of multiple types of cancers leading to fatality. Recent study identified essential role of this gene product in stem cell biology including normal embryogenesis, induced pluripotent stem cell (iPSC) generation and stem cell differentiation. Currently iPSC has become a prime choice as starting material for regenerative medicine to treat many diseases; however the relevant technology has many shortcomings. Our lab and others have been exploiting this protein for successful application in regenerative medicine that made it a blessed molecule. Here, based on the latest available information, we are concisely presenting these agonies and advantages of E-cadherin.