Predicted to enable RNA binding activity. Acts upstream of or within maturation of LSU-rRNA from tricistronic rRNA transcript (SSU-rRNA, 5.8S rRNA, LSU-rRNA); nucleolus organization; and protein localization to organelle. Located in condensed chromosome and nucleolus. Part of PeBoW complex. Is expressed in several structures, including alimentary system; brain; cardiovascular system; genitourinary system; and skeletal muscle. Orthologous to human PES1 (pescadillo ribosomal biogenesis factor 1). [provided by Alliance of Genome Resources, Apr 2022]