Enables palmitoyl-CoA 9-desaturase activity. Acts upstream of or within monounsaturated fatty acid biosynthetic process. Predicted to be located in endoplasmic reticulum and nucleolus. Predicted to be integral component of membrane. Predicted to be active in endoplasmic reticulum membrane. Predicted to be integral component of endoplasmic reticulum membrane. Is expressed in several structures, including alimentary system; nervous system; respiratory system; sensory organ; and skeleton. Human ortholog(s) of this gene implicated in autosomal dominant nonsyndromic deafness 79. Orthologous to several human genes including SCD (stearoyl-CoA desaturase). [provided by Alliance of Genome Resources, Apr 2022]