OCT3/4 (POU5F1) is a transcription factor that is expressed in stem cells and germ cells. Its expression is required to sustain cell self-renewal of undifferentiated stem cells. Oct-3/4 is the most recognized marker for totipotent ES cells. Ectopic expression of OCT3/4 has been used to produce iPS cells in culture. 

Human elongation factor-1 alpha (EF-1 alpha) is a constitutive promoter of human origin that can be used to drive ectopic gene expression in various in vitro and in vivo contexts. EF-1 alpha (or EF1a) is often useful in conditions where other promoters (such as CMV) have diminished activity or have been silenced (as in embryonic stem cells).