Model Description: A IRES-CreERT2 expression cassette was knocked into the Prl gene stop codon site. Prolactin (PRL) is a hormone synthesized and secreted by lactotroph cells in the anterior pituitary gland. PRL is responsible for lactogenesis and other processes associated with it. When crossed with a strain carrying a gene flanked by loxP sites, the flanked gene will be removed in cells expressing cre.