Most
genes considered master regulators code for
transcription factor proteins, which in turn alter the
expression of downstream genes in the pathway. Canonical examples of master regulators include
Oct-4 (also called POU5F1),
SOX2, and
NANOG, all transcription factors involved in maintaining
pluripotency in
stem cells. Other genes reported as master regulators code for
SR proteins, which function as
splicing factors, and some
noncoding RNAs. ==Criticism==