Efg1 is involved in rRNA processing [1, 2].

1: A panoramic view of yeast noncoding RNA processing. Peng WT, Robinson MD, Mnaimneh S, Krogan NJ, Cagney G, Morris Q, Davierwala AP, Grigull J, Yang X, Zhang W, Mitsakakis N, Ryan OW, Datta N, Jojic V, Pal C, Canadien V, Richards D, Beattie B, Wu LF, Altschuler SJ, Roweis S, Frey BJ, Emili A, Greenblatt JF, Cell 2003;113:919-933. PMID:12837249

2: Functional genomics of genes with small open reading frames (sORFs) in S. cerevisiae. Kastenmayer JP, Ni L, Chu A, Kitchen LE, Au WC, Yang H, Carter CD, Wheeler D, Davis RW, Boeke JD, Snyder MA, Basrai MA; Genome Res. 2006;16:365-373. PMID:16510898