RNA recognition motif (RRM) found in inner nuclear membrane protein Man1 (Man1) and similar proteinsThis subfamily corresponds to the RRM of Man1, also termed LEM domain-containing protein 3 (LEMD3), an integral protein of the inner nuclear membrane that binds to nuclear lamins and emerin, thus playing a role in nuclear organization. It is part of a protein complex essential for chromatin organization and cell division. It also functions as an important negative regulator for the transforming growth factor (TGF) beta/activin/Nodal signaling pathway by directly interacting with chromatin-associated proteins and transcriptional regulators, including the R-Smads, Smad1, Smad2, and Smad3. Moreover, Man1 is a unique type of left-right (LR) signaling regulator that acts on the inner nuclear membrane. Man1 plays a crucial role in angiogenesis. The vascular remodeling can be regulated at the inner nuclear membrane through the interaction between Man1 and Smads. Man1 contains an N-terminal LEM domain, two putative transmembrane domains, a MAN1-Src1p C-terminal (MSC) domain, and a C-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The LEM domain interacts with the DNA and chromatin-binding protein Barrier-to-Autointegration Factor, and is also necessary for efficient localization of MAN1 in the inner nuclear membrane. Research has indicated that C-terminal nucleoplasmic region of Man1 exhibits a DNA binding winged helix domain and is responsible for both DNA- and Smad-binding.