Purification of the spliced leader ribonucleoprotein particle from Leptomonas collosoma revealed the existence of an Sm protein in trypanosomes: Cloning the SmE homologue

23Citations
Citations of this article
14Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Trans-splicing in trypanosomes involves the addition of a common spliced leader (SL) sequence, which is derived from a small RNA, the SL RNA, to all mRNA precursors. The SL RNA is present in the cell in the form of a ribonucleoprotein, the SL RNP. Using conventional chromatography and affinity selection with 2'-O-methylated RNA oligonucleotides at high ionic strength, five proteins of 70, 16, 13, 12, and 8 kDa were co-selected with the SL RNA from Leptomonas collosoma, representing the SL RNP core particle. Under conditions of lower ionic strength, additional proteins of 28 and 20 kDa were revealed. On the basis of peptide sequences, the gene coding for a protein with a predicted molecular weight of 11.9 kDa was cloned and identified as homologue of the cis-spliceosomal SmE. The protein carries the Sm motifs 1 and 2 characteristic of Sm antigens that bind to all known cis-spliceosomal uridylic acid-rich small nuclear RNAs (U snRNAs), suggesting the existence of Sm proteins in trypanosomes. This finding is of special interest because trypanosome snRNPs are the only snRNPs examined to date that are not recognized by anti-Sm antibodies. Because of the early divergence of trypanosomes from the eukaryotic lineage, the trypanosome SmE protein represents one of the primordial Sm proteins in nature.

Cite

CITATION STYLE

APA

Goncharov, I., Palfi, Z., Bindereif, A., & Michaeli, S. (1999). Purification of the spliced leader ribonucleoprotein particle from Leptomonas collosoma revealed the existence of an Sm protein in trypanosomes: Cloning the SmE homologue. Journal of Biological Chemistry, 274(18), 12217–12221. https://doi.org/10.1074/jbc.274.18.12217

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free