Intermolecular interaction between a branching ribozyme and associated homing endonuclease mRNA

TY - JOUR

T1 - Intermolecular interaction between a branching ribozyme and associated homing endonuclease mRNA

AU - Birgisdottir, Asa B

AU - Nielsen, Henrik

AU - Beckert, Bertrand

AU - Masquida, Benoît

AU - Johansen, Steinar D

PY - 2011/5/1

Y1 - 2011/5/1

N2 - RNA tertiary interactions involving docking of GNRA (N; any base; R; purine) hairpin loops into helical stem structures on other regions of the same RNA are one of the most common RNA tertiary interactions. In this study, we investigated a tertiary association between a GAAA hairpin tetraloop in a small branching ribozyme (DiGIR1) and a receptor motif (HEG P1 motif) present in a hairpin structure on a separate mRNA molecule. DiGIR1 generates a 2′, 5′ lariat cap at the 5′ end of its downstream homing endonuclease mRNA by catalysing a self-cleavage branching reaction at an internal processing site. Upon release, the 5′ end of the mRNA forms a distinct hairpin structure termed HEG P1. Our biochemical data, in concert with molecular 3D modelling, provide experimental support for an intermolecular tetraloop receptor interaction between the L9 GAAA in DiGIR1 and a GNRA tetraloop receptor-like motif (UCUAAG-CAAGA) found within the HEG P1. The biological role of this interaction appears to be linked to the homing endonuclease expression by promoting post-cleavage release of the lariat capped mRNA. These findings add to our understanding of how protein-coding genes embedded in nuclear ribosomal DNA are expressed in eukaryotes and controlled by ribozymes.

AB - RNA tertiary interactions involving docking of GNRA (N; any base; R; purine) hairpin loops into helical stem structures on other regions of the same RNA are one of the most common RNA tertiary interactions. In this study, we investigated a tertiary association between a GAAA hairpin tetraloop in a small branching ribozyme (DiGIR1) and a receptor motif (HEG P1 motif) present in a hairpin structure on a separate mRNA molecule. DiGIR1 generates a 2′, 5′ lariat cap at the 5′ end of its downstream homing endonuclease mRNA by catalysing a self-cleavage branching reaction at an internal processing site. Upon release, the 5′ end of the mRNA forms a distinct hairpin structure termed HEG P1. Our biochemical data, in concert with molecular 3D modelling, provide experimental support for an intermolecular tetraloop receptor interaction between the L9 GAAA in DiGIR1 and a GNRA tetraloop receptor-like motif (UCUAAG-CAAGA) found within the HEG P1. The biological role of this interaction appears to be linked to the homing endonuclease expression by promoting post-cleavage release of the lariat capped mRNA. These findings add to our understanding of how protein-coding genes embedded in nuclear ribosomal DNA are expressed in eukaryotes and controlled by ribozymes.

U2 - 10.1515/bc.2011.055

DO - 10.1515/bc.2011.055

M3 - Journal article

C2 - 21495911

SN - 0021-9258

VL - 392

SP - 491

EP - 499

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

IS - 6

ER -