Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving antigen-antibody binding – specific binding protein...
Reexamination Certificate
1997-01-23
2002-02-12
Saunders, David (Department: 1644)
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving antigen-antibody binding, specific binding protein...
C435S007100, C435S007800, C435S007920, C435S007930, C436S501000
Reexamination Certificate
active
06346390
ABSTRACT:
INTRODUCTION
Technical Field
The field of this invention is the modulation of response to ligands by cell surface receptors.
Background
The complex regulatory balance between hormones, receptors and responding cells is critical to the correct functioning of multicellular organisms. Subtle environmental and genetic factors can disrupt this balance, sometimes resulting in disease. The advent of molecular biology has meant that medically important hormones can be made available in therapeutically useful amounts. Among them are human growth hormone, insulin-like growth factor, insulin, epidermal growth factor, and numerous others.
A condition of great economic and medical significance is insulin resistance, which is an essential feature of a great variety of clinical disorders, such as diabetes mellitus, obesity and certain types of hypertension. Individuals with non-insulin dependent diabetes present with insulin resistance in peripheral tissues. They have a subnormal glucose utilization in skeletal muscle, where glucose transport across the cell membrane of skeletal muscle is the rate limiting step in glucose metabolism. It is possible that a defect exists in insulin-dependent glucose transport in skeletal muscle in diabetic states, where decreased levels of the glucose transporter 4 protein (GLUT4) have been observed. In adipose and muscle cells, insulin stimulates a rapid and dramatic increase in glucose uptake, primarily by promoting the redistribution of the GLUT4 glucose transporter from its intracellular storage site to the plasma membrane.
Insulin resistance may also be attributed to a defect in insulin action at the cellular level. The insulin receptor is activated by binding of insulin to the alpha-subunit of the receptor, which causes autophosphorylation of the intracellular beta-subunit region. The activated insulin receptor couples to cytosolic receptor substrates that can affect signaling cascades, resulting in the pleiotropic hormone response. Most proteins involved in the signal transduction pathway are not known yet, but each of them might play a role in the various forms of insulin resistance. The heterogeneous nature of insulin resistance makes treatments that can act “upstream” of the signal transduction pathways very attractive, because a number of different pathologies could be treated with a single drug.
Specific peptides have been previously shown to enhance the cellular response to certain hormones. This effect has been attributed to inhibition of the internalization of the corresponding hormone receptors. Insulin-stimulated glucose uptake is increased by adding the peptides to responding cells, offering the possibility of improved therapy for insulin dependent and insulin resistant diabetes. The enhanced response may also be exploited in therapies involving other hormones. Improvements in the specificity of agents that enhance the activity of insulin and other hormones are of considerable interest for their therapeutic benefits. The site of action for such peptides on receptors molecules is of interest for drug evaluation and design.
Relevant Literature
Several groups have examined the glucose transporter and insulin receptor for residues that are involved in internalization. Rajagopalan et al. (1995)
Biochem. Biophys. Res. Commun.
211:714-8 found that residues GPYL950-953 served as the predominant endocytosis signal and the sequence NPEY957-960 as a secondary signal. Levy-Toledano et al. (1993)
Biochem. Biophys. Acta.
1220:1-14 suggest that the structural domain located 43-113 amino acids from the C-terminus is required in intact cells for insulin-stimulated autophosphorylation and signal transmission. Verhey et al. (1995)
J. Cell Biol.
130:1071-9 identified sequences involved in the differential subcellular localization and hormone-responsiveness of glucose transporter isoforms. The COOH-terminal 30 amino acids of GLUT4 are sufficient for its correct localization to an intracellular storage pool that translocates to the cell surface in response to insulin.
U.S. Pat. No. 5,385,888, issued Jan. 31, 1995, describes Class I MHC peptide modulation of surface receptor activity. Data presented in International patent application PCT/US94/09189 suggest that these peptides must be in an ordered conformation to be biologically active. The composition and uses of such peptides are further described in International application PCT/US93/01758. The peptides are further disclosed in International application PCTIUS89/00876.
Regulation of receptor internalization by the major histocompatibility complex class I molecule is shown by Olsson et al. (1994)
Proc. Natl. Acad. Sci.
91:9086-90. Peptides derived from the alpha 1 domain of the major histocompatibility complex class I protein (MHC-I) inhibit internalization of some receptors, thereby increasing the steady-state number of active receptors on the cell surface. It is suggested that MHC-I participates in the regulation of cell surface receptor activity. Stagsted et al. (1993)
J. Biol. Chem.
268:22809-13 demonstrate that such peptides inhibit the internalization of glucose transporters (GLUT4) and insulin-like growth factor II (IGF-II) receptors in insulin-stimulated cells.
SUMMARY OF THE INVENTION
Methods and compositions are provided for determining, in a cell surface receptor protein, an extracytoplasmic region that is involved with internalization. Identification of the amino acid sequence in this region permits the design of drug screening assays for bioactive compounds that modulate receptor internalization. Oligopeptides, having at least substantially the amino acid sequence of that portion of that receptor's extracellular domain, modulate the response of cell surface receptors to ligand binding.
The receptor derived peptides have sequence similarity to previously described regulatory peptides from the major histocompatibility complex class I antigens. The methods and compositions of the subject invention are used in diagnosis and therapy of diseases that involve inadequate or inappropriate receptor response as well as in the screening of drug candidates that affect surface expression of receptors. Also useful for drug screening is a modified receptor molecule, where the sequence corresponding to the regulatory peptide is modified or deleted.
DATABASE REFERENCES FOR NUCLEOTIDE AND AMINO ACID SEQUENCES
The complete mRNA sequence encoding the human insulin responsive glucose transporter (GLUT4) has the Genbank accession number M2O747, published by Fukumoto et al. (1989)
J. Biol. Chem.
264:7776-7779. The complete mRNA sequence encoding the human insulin receptor has the Genbank accession number A18657, published in International Patent Application No. WO/91/17253. The complete mRNA sequence encoding the human leptin receptor has the Genbank accession number U43168, and was published by Tartaglia et al. (1995)
Cell
83:1263-1271. The DNA sequence encoding the human granulocyte colony stimulating factor (G-CSF) receptor has the EMBL accession numbers M5982O, M38O27, X5572O and X55721, and was published by Larsen et al. (1990)
J. Exp. Med.
172:1559-1570. The complete sequence of the human interleukin 2 (IL-2) receptor has the Swissprot accession number P01589, and was published by Leonard et al. (1984)
Nature
311:626-631. The complete sequence of the human epidermal growth factor (EGF) receptor has the Swissprot accession number P00533, and was published by Ullrich et al. (1984)
Nature
309:418-425. The sequences for other cell surface receptors are known, and easily ascertainable by those in the art.
The sequences of known HLA and H-2 alleles may be found in Kabat et al. (1991)
Sequences of Proteins of Immunological Interest
, N.I.H. publication no. 91-3242, vol. 1, pp. 738-740, 761, 770-771, 779-780, 788-789 and 802-804.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
The present invention is based on the discovery that sequences on the extracellular portion of cell surface receptors, “internalization sequences”, bind to each other to prevent internalization of the receptors. Fortuitously, the int
Navrenda Tatajna
Olsson Lennart
Receptron, Inc.
Saunders David
LandOfFree
Receptor derived peptides involved in modulation of response... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Receptor derived peptides involved in modulation of response..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Receptor derived peptides involved in modulation of response... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2970513