The Stat3/5 locus encodes novel endoplasmic reticulum and helicase-like proteins that are preferentially expressed in normal and neoplastic mammary tissue

Genomics. 2001 Dec;78(3):129-34. doi: 10.1006/geno.2001.6661.


The signal transducers and activators of transcription (STAT) 5 and 3 are critical for mammary alveolar development during pregnancy and remodeling during involution. In the mouse, STAT3, STAT5a, and STAT5b are encoded by adjacent genes on chromosome 11 (60.5 cM). To identify additional genes in the Stat3/5 locus that may participate in normal and neoplastic development of the mammary gland, we have cloned and sequenced 500 kb and searched for genes preferentially expressed in mammary tissue. We identified six known genes and cloned two new genes, termed D11Lgp1 and D11Lgp2. Both genes are most highly expressed in normal mammary tissue and mammary tumors from several transgenic mouse models. LGP1 consists of 532 and 530 amino acids in mouse and human, respectively (88% similarity). A region in the carboxy-terminal half of LGP1 has limited homology with Arabidopsis thaliana GH3-like proteins. Immunofluorescence studies demonstrated that LGP1 is located in the nuclear envelope and the endoplasmic reticulum. LGP2 is a cytoplasmic protein of 678 amino acids.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • DNA Helicases / genetics*
  • DNA-Binding Proteins / genetics*
  • Endoplasmic Reticulum / metabolism*
  • Humans
  • Mammary Glands, Animal / metabolism*
  • Mammary Neoplasms, Experimental / genetics*
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics*
  • Membrane Proteins / metabolism
  • Mice
  • Milk Proteins*
  • Molecular Sequence Data
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • STAT3 Transcription Factor
  • STAT5 Transcription Factor
  • Sequence Homology, Amino Acid
  • Trans-Activators / genetics*
  • Tumor Suppressor Proteins


  • D11Lgp1e protein, mouse
  • DNA-Binding Proteins
  • Membrane Proteins
  • Milk Proteins
  • RNA, Messenger
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • STAT5 Transcription Factor
  • STAT5A protein, human
  • STAT5B protein, human
  • Stat3 protein, mouse
  • Stat5a protein, mouse
  • Stat5b protein, mouse
  • Trans-Activators
  • Tumor Suppressor Proteins
  • DNA Helicases