# Variation in the ribosome interacting loop of the Sec61α from Giardia lamblia

## TL;DR

This paper shows that Giardia lamblia uses a lysine instead of arginine to interact with ribosomes, possibly due to its G-rich rRNA.

## Contribution

The study identifies a functional substitution of arginine with lysine in Giardia lamblia's Sec61α for ribosome interaction.

## Key findings

- Giardia lamblia's Sec61α uses lysine instead of arginine for ribosome interaction.
- This substitution may accommodate the G-rich rRNA in Giardia lamblia.

## Abstract

The interaction between the ribosome and the endoplasmic reticulum-located Sec61 protein translocon is mediated through an arginine residue of Sec61α, which is conserved in all prokaryotic and eukaryotic orthologues characterized to date. Using in silico approaches we report that instead of arginine, this ribosome-interaction function is most likely discharged by a lysine residue in the protist Giardia lamblia. This functional substitution of the R with a K in GlSec61α may have taken place to accommodate a G-rich rRNA.

The online version of this article (doi:10.1186/s13062-015-0087-0) contains supplementary material, which is available to authorized users.