Transcription factor regulating MHC expression, CDNA and genomic clones encoding same and retroviral expression constructs thereof

• US 5,840,832 A
• Filed: 10/21/1994
• Issued: 11/24/1998
• Est. Priority Date: 10/21/1994
• Status: Expired due to Fees

• Current Assignee: President and Fellows of Harvard College (Harvard Corporation), Johns Hopkins University
• Original Assignee: President and Fellows of Harvard College (Harvard Corporation), Johns Hopkins University
• Inventors: Strominger, Jack L., Ono, Santa Jeremy
• Primary Examiner(s): Elliott, George C.
• Assistant Examiner(s): Wai, Thanda
• Application Number:
  US08/327,832
• Time in Patent Office: 1,495 Days
• Field of Search: 530/350, 530/300, 435/320.1
• US Class Current: 530/300
• CPC Class Codes: A61K 38/00 Medicinal preparations containing peptides peptides containing beta-lactam rings A61K31/00; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, A61K31/00; ergot alkaloids of the cyclic peptide type A61K31/48; containing macromolecular compounds having statistically distributed amino acid units A61K31/74; medicinal preparations containing antigens or antibodies A61K39/00; medicinal preparations characterised by the non-active ingredients, e.g. peptides as drug carriers, A61K47/00
• CPC Class Codes: C07K 14/4703 Inhibitors; Suppressors
• CPC Class Codes: C07K 2319/00 Fusion polypeptide

Abstract

The present invention relates to NF-X1, a novel DNA binding protein which regulates expression of major histocompatibility complex (MHC) class II molecules, and to DNA sequences which encode the protein as well as recombinant expression of the protein. NF-X1 is a newly identified, cysteine-rich polypeptide which interacts sequence-specifically with the conserved X1 box regulatory element found in the proximal promoters of class II MHC genes. A cysteine-rich domain within NF-X1 contains a motif repeated seven times, and this entire region is necessary and sufficient for both sequence specific binding and effector function. The motif is related to but distinct from the previously described metal-binding protein families: LIM domain and RING finger. NFX.1 mRNA is markedly overexpressed late after induction of cells with interferon-gamma, and this overexpression coincides with a reduction in the level of HLA-DRA transcript in these cells. Overexpression of this protein strongly and specifically represses the transcription of the HLA-DRA gene in MHC class II positive cell lines, indicating that the NF-X1 protein is a transcriptional repressor of MHC class II molecules.

Claims

1. A substantially pure polypeptide which contains at least about five copies of a cysteine rich sequence according to SEQ ID NO:

1 coupled to a cysteine rich sequence according to SEQ ID NO;

2 by a bridge peptide of from one to five amino acids, said polypeptide specifically binding to double stranded DNA having a sequence according to SEQ ID NO;

3.

2. A substantially pout polypeptide selected from the group consisting of nuclear factor-X1, a truncation of nuclear factor-X1, and fusion proteins containing them, wherein said polypeptide specifically binds to double stranded DNA having the sequence of SEQ ID NO:

3.

3. The substantially pure polypeptide of claim 2, said polypeptide having a sequence corresponding to the sequence of SEQ ID NO:

5.

4. The polypeptide of claim 3, encoded by plasmid clone-16 deposited under ATCC Accession No. 75895.

5. The polypeptide of claim 3, having the sequence of SEQ ID NO:

5.