This is a domain found in groups II and III of Schlafen (SLFN), protein which follows the AlbA_2 domain (Pfam:PF04326). In group II this is the C-terminal domain, while in group III members it localizes in the central region, followed by a C-terminal helicase domain (Pfam:PF09848). This domain has been described as a GTPase-like domain and it contains the SLFN-specific SWADL motif [1-5]. SLFN proteins are involved in the control of cell proliferation, induction of immune responses, and the regulation of viral replication. Mouse and human members are regulated by interferons [3]. In SLFN12, this is the C-terminal domain which contains crucial residues for interaction with PDE3A [1]. By analogy with dynamin and MxB, this domain in SLFN12 may contribute to chromatin and actin cytoskeleton interactions, involved in cell differentiation [4]. SLFN proteins share common domains and a high degree of homology, however, they have specific and sometimes, opposing effects in some cancer types [5].

1: Structure of PDE3A-SLFN12 complex and structure-based design for a potent apoptosis inducer of tumor cells. Chen J, Liu N, Huang Y, Wang Y, Sun Y, Wu Q, Li D, Gao S, Wang HW, Huang N, Qi X, Wang X; Nat Commun. 2021;12:6204. PMID:34707099

2: Structure of PDE3A-SLFN12 complex reveals requirements for activation of SLFN12 RNase. Garvie CW, Wu X, Papanastasiou M, Lee S, Fuller J, Schnitzler GR, Horner SW, Baker A, Zhang T, Mullahoo JP, Westlake L, Hoyt SH, Toetzl M, Ranaghan MJ, de Waal L, McGaunn J, Kaplan B, Piccioni F, Yang X, Lange M, Tersteegen A, Raymond D, Lewis TA, Carr SA, Cherniack AD, Lemke CT, Meyerson M, Greulich H; Nat Commun. 2021;12:4375. PMID:34272366

3: The schlafen family of proteins and their regulation by interferons. Mavrommatis E, Fish EN, Platanias LC; J Interferon Cytokine Res. 2013;33:206-210. PMID:23570387

4: Deciphering the three-domain architecture in schlafens and the structures and roles of human schlafen12 and serpinB12 in transcriptional regulation. Chen J, Kuhn LA; J Mol Graph Model. 2019;90:59-76. PMID:31026779

5: Schlafens: Emerging Proteins in Cancer Cell Biology. Al-Marsoummi S, Vomhof-DeKrey EE, Basson MD; Cells. 2021; [Epub ahead of print] PMID:34571887