Predicted cross-reactivity based on sequence identity: Mouse, Rat, Canine.

Stem cells are crucial ingredients in the progressive restriction of cellular developmental capacity during mammalian embryogenesis. Until recently, only embryonic stem cells (ESC) had been shown to exhibit the potential to differentiate into cells of the all three germ layers. However, adult stem cells (ASC) can regain pluripotency (potential to differentiate into various lineages) if transferred from one stem-cell microenvironment into another. The transcription factor OCT4, expressed in ESCs and germ cells, is strongly implicated in the process of maintaining as well as regaining stem-cell pluripotency and functions as a key regulator of mammalian germline development.

Reacts with Human.

Transcription factors containing the POU homeodomain have been shown to be important regulators of tissue-specific gene expression in lymphoid and pituitary differentiation and in early mammalian development. Two forms of OCT3 mRNA are expressed in adult tissues as a result of alternative splicing–OCT3A and OCT3B. Reverse transcriptase PCR showed low level of expression in both OCT3A and OCT3B mRNA in all adult human tissues examined. Oct3 is present in mouse oocytes before and after fertilization. When fertilized oocytes were injected with antisense Oct3 oligonucleotides or double-stranded DNA containing the octamer motif, embryonic DNA synthesis was inhibited and the embryos were arrested at the one-cell stage.