This domain is found towards the N-terminal of eukaryotic proteins including U3 small nucleolar RNA-associated protein 20 (UTP20) from yeast and the homologue from human, also known as DRIM (Down-Regulated In Metastasis) (Swiss:O75691), which is differentially expressed in metastatic and non-metastatic human breast carcinoma cells [1]. Proteins of this entry are involved in processing of non-coding RNA as components of of the small-subunit (SSU) processome; SSU processome is involved in the biogenesis of the 18S rRNA [2,3]. UTP20 is a huge alpha-solenoid structure that functions as a scaffold [4,5].

1: Differential gene expression in mammary carcinoma cell lines: identification of DRIM, a new gene down-regulated in metastasis. Schwirzke M, Gnirke A, Bork P, Tarin D, Weidle UH; Anticancer Res 1998;18:1409-1421. PMID:9673349

2: 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

3: Human 1A6/DRIM, the homolog of yeast Utp20, functions in the 18S rRNA processing. Wang Y, Liu J, Zhao H, Lu W, Zhao J, Yang L, Li N, Du X, Ke Y; Biochim Biophys Acta. 2007;1773:863-868. PMID:17498821

4: 90S pre-ribosome transformation into the primordial 40S subunit. Cheng J, Lau B, La Venuta G, Ameismeier M, Berninghausen O, Hurt E, Beckmann R; Science. 2020;369:1470-1476. PMID:32943521

5: Cryo-EM structure of 90S small ribosomal subunit precursors in transition states. Du Y, An W, Zhu X, Sun Q, Qi J, Ye K; Science. 2020;369:1477-1481. PMID:32943522