National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
NIHGM129430, NIHGM145888
米国
引用
ジャーナル: Cell / 年: 2024 タイトル: The CRISPR-associated adenosine deaminase Cad1 converts ATP to ITP to provide antiviral immunity. 著者: Christian F Baca / Puja Majumder / James H Hickling / Linzhi Ye / Marianna Teplova / Sean F Brady / Dinshaw J Patel / Luciano A Marraffini / 要旨: Type III CRISPR systems provide immunity against genetic invaders through the production of cyclic oligo-adenylate (cA) molecules that activate effector proteins that contain CRISPR-associated ...Type III CRISPR systems provide immunity against genetic invaders through the production of cyclic oligo-adenylate (cA) molecules that activate effector proteins that contain CRISPR-associated Rossman fold (CARF) domains. Here, we characterized the function and structure of an effector in which the CARF domain is fused to an adenosine deaminase domain, CRISPR-associated adenosine deaminase 1 (Cad1). We show that upon binding of cA or cA to its CARF domain, Cad1 converts ATP to ITP, both in vivo and in vitro. Cryoelectron microscopy (cryo-EM) structural studies on full-length Cad1 reveal an hexameric assembly composed of a trimer of dimers, with bound ATP at inter-domain sites required for activity and ATP/ITP within deaminase active sites. Upon synthesis of cA during phage infection, Cad1 activation leads to a growth arrest of the host that prevents viral propagation. Our findings reveal that CRISPR-Cas systems employ a wide range of molecular mechanisms beyond nucleic acid degradation to provide adaptive immunity in prokaryotes.
A: Adenosine deaminase domain-containing protein B: Adenosine deaminase domain-containing protein C: Adenosine deaminase domain-containing protein D: Adenosine deaminase domain-containing protein