MAN1, an inner nuclear membrane protein that shares the LEM domain with lamina-associated polypeptide 2 and emerin

J Biol Chem. 2000 Feb 18;275(7):4840-7. doi: 10.1074/jbc.275.7.4840.


The "MAN antigens" are polypeptides recognized by autoantibodies from a patient with a collagen vascular disease and localized to the nuclear envelope. We now show that one of the human MAN antigens termed MAN1 is a 82.3-kDa protein with an amino-terminal domain followed by two hydrophobic segments and a carboxyl-terminal tail. The MAN1 gene contains seven protein-coding exons and is assigned to human chromosome 12q14. Its mRNA is approximately 5.5 kilobases and is detected in several different cell types that were examined. Cell extraction experiments show that MAN1 is an integral membrane protein. When expressed in transfected cells, MAN1 is exclusively targeted to the nuclear envelope, consistent with an inner nuclear membrane localization. Protein sequence analysis reveals that MAN1 shares a conserved globular domain of approximately 40 amino acids, which we term the LEM module, with inner nuclear membrane proteins lamina-associated polypeptide 2 and emerin. The LEM module is also present in two proteins of Caenorhabditis elegans. These results show that MAN1 is an integral protein of the inner nuclear membrane that shares the LEM module with other proteins of this subcellular localization.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Caenorhabditis elegans Proteins*
  • Chromosomes, Human, Pair 12
  • DNA Primers
  • DNA, Complementary
  • DNA-Binding Proteins*
  • HeLa Cells
  • Humans
  • Membrane Proteins / chemistry*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Nuclear Envelope / metabolism*
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • RNA, Messenger / genetics
  • Sequence Homology, Amino Acid
  • Thymopoietins / chemistry*


  • Caenorhabditis elegans Proteins
  • DNA Primers
  • DNA, Complementary
  • DNA-Binding Proteins
  • LEMD3 protein, human
  • Membrane Proteins
  • Nuclear Proteins
  • RNA, Messenger
  • Thymopoietins
  • emerin
  • lamina-associated polypeptide 2
  • lem-2 protein, C elegans

Associated data

  • GENBANK/AF112299
  • GENBANK/AF112300
  • GENBANK/AF180135
  • GENBANK/AF180136
  • GENBANK/AF180137
  • GENBANK/AF180138
  • GENBANK/AF180139
  • GENBANK/AF180140
  • GENBANK/AF180141
  • GENBANK/AF180142