Assembly of a fragmented ribonucleotide reductase by protein interaction domains derived from a mobile genetic element.
Nucleic Acids Res
; 39(4): 1381-9, 2011 Mar.
Article
en En
| MEDLINE
| ID: mdl-20972217
ABSTRACT
Ribonucleotide reductase (RNR) is a critical enzyme of nucleotide metabolism, synthesizing precursors for DNA replication and repair. In prokaryotic genomes, RNR genes are commonly targeted by mobile genetic elements, including free standing and intron-encoded homing endonucleases and inteins. Here, we describe a unique molecular solution to assemble a functional product from the RNR large subunit gene, nrdA that has been fragmented into two smaller genes by the insertion of mobE, a mobile endonuclease. We show that unique sequences that originated during the mobE insertion and that are present as C- and N-terminal tails on the split NrdA-a and NrdA-b polypeptides, are absolutely essential for enzymatic activity. Our data are consistent with the tails functioning as protein interaction domains to assemble the tetrameric (NrdA-a/NrdA-b)(2) large subunit necessary for a functional RNR holoenzyme. The tails represent a solution distinct from RNA and protein splicing or programmed DNA rearrangements to restore function from a fragmented coding region and may represent a general mechanism to neutralize fragmentation of essential genes by mobile genetic elements.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Ribonucleótido Reductasas
/
Secuencias Repetitivas Esparcidas
Idioma:
En
Revista:
Nucleic Acids Res
Año:
2011
Tipo del documento:
Article
País de afiliación:
Suecia