Crystal structure and functional analysis of an archaeal chromatin protein Alba from the hyperthermophilic archaeon Pyrococcus horikoshii OT3

• Published in: Bioscience, biotechnology, and biochemistry biotechnology, and biochemistry, 2008-03, Vol.72 (3), p.749-758
• Main Authors: Hada, K.(Kyushu Univ., Fukuoka (Japan)), Nakashima, T, Osawa, T, Shimada, H, Kakuta, Y, Kimura, M
• Format: Article
• Language: English
• Subjects: Alba; Arabidopsis; Archaeal Proteins - chemistry; Archaeal Proteins - metabolism; Archaeal Proteins - physiology; ARN DE TRANSFERENCIA; ARN DE TRANSFERT; BACILLUS STEAROTHERMOPHILUS; Biological and medical sciences; CHROMATIN; CHROMATINE; CROMATINA; crystal structure; Crystallography, X-Ray; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - metabolism; DNA-Binding Proteins - physiology; Fundamental and applied biological sciences. Psychology; MICRO-ORGANISME THERMOPHILE; MICROORGANISMOS TERMOFILOS; precursor tRNA (pre-tRNA); Protein Binding; Protein Conformation; PROTEINAS; PROTEINE; PROTEINS; Pyrococcus horikoshii; Pyrococcus horikoshii - chemistry; RIBONUCLEASAS; RIBONUCLEASE; ribonuclease P (RNase P); Ribonuclease P - metabolism; RIBONUCLEASES; RNA Precursors - metabolism; RNA, Archaeal - metabolism; RNA, Transfer, Tyr - metabolism; TEMPERATURA; TEMPERATURE; THERMOPHILIC MICROORGANISMS; TRANSFER RNA
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.70639

The crystal structure of the Alba protein (PhoAlba) from a hyperthermophilic archaeon, Pyrococcus horikoshii OT3, was determined at a resolution of 2.8 angstrom. PhoAlba structurally belongs to the alpha/beta proteins and is similar not only to archaeal homologues but also to RNA-binding proteins, including the C-terminal half of initiation factor 3 (IF3-C) from Bacillus stearothermophilus, an Escherichia coli protein implicated in cell division (Yhhp), and an Arabidopsis protein of unknown function. We found by gel shift assay that PhoAlba interacts with both ribonuclease P (RNase P) RNA (PhopRNA) and precursor-tRNAsup(Tyr)(pre-tRNAsup(Tyr)) in P. horikoshii. However, the addition of PhoAlba to reconstituted particles composed of PhopRNA and four or five protein subunits had little influence on either the pre-tRNA processing activity or the optimum temperature for the processing activity. These results suggest that PhoAlba contributes little to the catalytic activity of P. horikoshii RNase P.