Selective oxidation of 5-methylcytosine by TET-family proteins

• US 10,465,234 B2
• Filed: 10/24/2018
• Issued: 11/05/2019
• Est. Priority Date: 09/26/2008
• Status: Active Grant

• Current Assignee: Children's Medical Center Corporation, United States Department Of Health And Human Services (Government of the United States of America)
• Original Assignee: Children's Medical Center Corporation
• Inventors: Rao, Anjana, Tahiliani, Mamta, Koh, Kian Peng, Agarwal, Suneet, Iyer, Aravind
• Primary Examiner(s): Claytor, Renee
• Assistant Examiner(s): Clarke, Trent R
• Application Number:
  US16/169,801
• Publication Number:
  US 20190048405A1
• Time in Patent Office: 377 Days
• Field of Search: None
• CPC Class Codes: C12N 2501/70 Enzymes
• CPC Class Codes: C12N 2501/71 Oxidoreductases (EC 1.)
• CPC Class Codes: C12N 2501/724 Glycosyltransferases (EC 2.4.)
• CPC Class Codes: C12N 9/0071 acting on paired donors with incorporation of molecular oxygen (1.14)
• CPC Class Codes: C12N 9/1007 Methyltransferases (general) (2.1.1.)
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: C12Q 1/6806 Preparing nucleic acids for analysis, e.g. for polymerase chain reaction [PCR] assay C12Q1/6804 takes precedence
• CPC Class Codes: C12Q 1/6827 for detection of mutation or polymorphism
• CPC Class Codes: C12Q 1/6869 Methods for sequencing
• CPC Class Codes: C12Q 2521/531 Glycosylase
• CPC Class Codes: C12Q 2522/10 Nucleic acid binding proteins
• CPC Class Codes: C12Q 2537/164 Methylation detection other then bisulfite or methylation sensitive restriction endonucleases
• CPC Class Codes: C12Q 2600/154 Methylation markers
• CPC Class Codes: G01N 2500/00 Screening for compounds of potential therapeutic value
• CPC Class Codes: G01N 33/5011 for testing antineoplastic activity
• CPC Class Codes: G01N 33/5308 for analytes not provided for elsewhere, e.g. nucleic acids, uric acid, worms, mites

Abstract

The present invention provides for novel methods for regulating and detecting the cytosine methylation status of DNA. The invention is based upon identification of a novel and surprising catalytic activity for the family of TET proteins, namely TET1, TET2, TET3, and CXXC4. The novel activity is related to the enzymes being capable of converting the cytosine nucleotide 5-methylcytosine into 5-hydroxymethylcytosine by hydroxylation.

Claims

1. A method comprising:

administering to a subject, an agent that modulates activity of an enzyme that mediates conversion of a methylated cytosine residue to a modified base, wherein said subject has a cancer or is at risk of developing said cancer, wherein said modified base comprises a hydroxymethylated cytosine residue and wherein said agent comprises a siRNA.

2. The method of claim 1, wherein said subject is a mammal.

3. The method of claim 2, wherein said methylated cytosine residue comprises a 5-methylcytosine.

4. The method of claim 2, wherein said hydroxymethylated cytosine residue is a 5-hydroxymethylcytosine.

5. The method of claim 2, wherein said cancer is leukemia.

6. The method of claim 5, wherein said leukemia is myeloid leukemia.

7. The method of claim 2, wherein said agent inhibits activity of said enzyme.

8. The method of claim 2, wherein said enzyme comprises a TET family enzyme, functional TET family derivative, or a TET catalytically active fragment.

9. The method of claim 8, wherein said TET family enzyme comprises TET1, TET2, TET3 or CXXC4.

10. The method of claim 8, wherein said functional TET family derivative comprises SEQ ID NO:

1.

11. The method of claim 8, wherein said TET catalytically active fragment comprises SEQ ID NO:

2, SEQ ID NO;

3, SEQ ID NO;

4, or SEQ ID NO;

5.