Coupling transcriptional activation of CRISPR–Cas system and DNA repair genes by Csa3a in Sulfolobus islandicus

TY - JOUR

T1 - Coupling transcriptional activation of CRISPR–Cas system and DNA repair genes by Csa3a in Sulfolobus islandicus

AU - Liu, Tao

AU - Liu, Zhenzhen

AU - Ye, Qing

AU - Pan, Saifu

AU - Wang, Xiaodi

AU - Li, Yingjun

AU - Peng, Wenfang

AU - Liang, Yunxiang

AU - She, Qunxin

AU - Peng, Nan

PY - 2017/9/1

Y1 - 2017/9/1

N2 - CRISPR-Cas system provides the adaptive immunity against invading genetic elements in prokaryotes. Recently, we demonstrated that Csa3a regulator mediates spacer acquisition in Sulfolobus islandicus by activating the expression of Type IA adaptation cas genes. However, links between the activation of spacer adaptation and CRISPR transcription/processing, and the requirement for DNA repair genes during spacer acquisition remained poorly understood. Here, we demonstrated that de novo spacer acquisition required Csa1, Cas1, Cas2 and Cas4 proteins of the Sulfolobus Type IA system. Disruption of genes implicated in crRNA maturation or DNA interference led to a significant accumulation of acquired spacers, mainly derived from host genomic DNA. Transcriptome and proteome analyses showed that Csa3a activated expression of adaptation cas genes, CRISPR RNAs, and DNA repair genes, including herA helicase, nurA nuclease and DNA polymerase II genes. Importantly, Csa3a specifically bound the promoters of the above DNA repair genes, suggesting that they were directly activated by Csa3a for adaptation. The Csa3a regulator also specifically bound to the leader sequence to activate CRISPR transcription in vivo. Our data indicated that the Csa3a regulator couples transcriptional activation of the CRISPR-Cas system and DNA repair genes for spacer adaptation and efficient interference of invading genetic elements.

AB - CRISPR-Cas system provides the adaptive immunity against invading genetic elements in prokaryotes. Recently, we demonstrated that Csa3a regulator mediates spacer acquisition in Sulfolobus islandicus by activating the expression of Type IA adaptation cas genes. However, links between the activation of spacer adaptation and CRISPR transcription/processing, and the requirement for DNA repair genes during spacer acquisition remained poorly understood. Here, we demonstrated that de novo spacer acquisition required Csa1, Cas1, Cas2 and Cas4 proteins of the Sulfolobus Type IA system. Disruption of genes implicated in crRNA maturation or DNA interference led to a significant accumulation of acquired spacers, mainly derived from host genomic DNA. Transcriptome and proteome analyses showed that Csa3a activated expression of adaptation cas genes, CRISPR RNAs, and DNA repair genes, including herA helicase, nurA nuclease and DNA polymerase II genes. Importantly, Csa3a specifically bound the promoters of the above DNA repair genes, suggesting that they were directly activated by Csa3a for adaptation. The Csa3a regulator also specifically bound to the leader sequence to activate CRISPR transcription in vivo. Our data indicated that the Csa3a regulator couples transcriptional activation of the CRISPR-Cas system and DNA repair genes for spacer adaptation and efficient interference of invading genetic elements.

U2 - 10.1093/nar/gkx612

DO - 10.1093/nar/gkx612

M3 - Journal article

C2 - 28911114

SN - 0305-1048

VL - 45

SP - 8978

EP - 8992

JO - Nucleic Acids Research

JF - Nucleic Acids Research

IS - 15

M1 - gkx612

ER -