Embryonic Stem Cells

By Jamshed Arslan, Pharm D, PhD

Transforming growth factor beta (TGF beta) signaling along with its family members have been implicated in development and maintenance of various organs. Stem cells are important contributors to this process and are characterized by their ability to self-renew and to generate differentiated cells of a particular tissue. Stem cells can be classified into embryonic and somatic stem cells.

The jumonji (JMJ) gene, obtained by a gene trap strategy, is essential for embryogenesis and is suggested to play important roles in cell growth during development. The amino acid sequence of the JMJ protein includes a nuclear localization signal and a DNA binding motif called the AT-rich interactive domain (ARID). Unlike the other members of the JARID family of proteins, JARID2 has a long N-terminal moiety devoid of characterized domains.

Beclin 1 is the mammalian orthologue of the yeast Apg6/Vps30 gene. Beclin 1 can complement the defect in autophagy present in apg6 yeast strains and stimulate autophagy when overexpressed in mammalian cells (1) and can bind to Bcl2, an important regulator of apoptosis (2) suggesting a role in two fundamentally important cellular pathways: autophagy and apoptosis.

Epigenetic alterations have come to prominence in biomedical research. In particular, hypermethylation of CpG islands located in the promoter regions of tumor-suppressor genes is now firmly established as an important mechanism for gene inactivation in cancer.

Caspase 3 is a member of the cysteine-aspartic acid protease family and an important mediator of apoptosis. Caspase 3 antibody reagents have been used in cancer, Alzheimer's disease and stem cell research. A recent caspase 3 antibody ELISA study showed elevated levels of the p17 caspase 3 fragment were associated with myocardial infarction in humans.

We at Novus Biologicals recently extended our antibody catalog to include several embryonic stem cells (ESC) antibodies validated for use in FACS (fluorescent activated cell sorting) assays. Among them was Oct4, which recently became the focus of an interesting study into the human aging process.