I/We Claim:
1. A degree comprising an amino acid sequence having at least 70 % sequence
identity to an amino acid sequence as set forth in SEQ ID NO: 1 for
regulating the expression of a protein.
5 2. The degree as claimed in claim 1, wherein the degree comprises an amino
acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ
ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7,
and SEQ ID NO: 8.
3. The degron as claimed in claim 1 or claim 2, wherein the degree is encoded
10 by a nucleotide sequence, having a sequence selected from the group
consisting of SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID
NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, and SEQ ID
NO: 16.
4. The degron as claimed in claim 1, wherein the degron is present at the C15 terminus of the protein.
5. A fusion protein, comprising:
a) a polypeptide of interest; and
b) the degron as claimed in claim 1;
wherein the degron is operable linked to the polypeptide of interest;
20 and the fusion protein has an amino acid sequence selected from a
group consisting of SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19,
and SEQ ID NO: 20.
6. The fusion protein as claimed in claim 5, wherein the fusion protein
further comprises a tag and/or a detectable label.
25 7. The fusion protein as claimed in claim 6, wherein the tag is selected from
FLAG, HA, myc, His, GST, V5, MBP, or Biotin; and the detectable label is
selected from fluorescent label (GFP, m Cherry, REP, DsRed, YFP, CFP),
or luminescent label (Firefly luciferase, Renilla luciferase, nanoLuc,
Gaussia luciferase).
20
8. The fusion protein as claimed in claim 5, wherein the polypeptide of
interest is selected from the group consisting of GFP, MTCH, Renilla
luciferase, and mtDsRed.
9. A polynucleotide encoding the fusion protein as claimed in claim 5.
5 10. The polynucleotide as claimed in claim 9, wherein the polynucleotide has
a nucleotide sequence selected from the group consisting of SEQ ID NO:
21, SEQ ID MO: 22, SEQ ID NO: 23, and SEQ ID NO: 24.
11. A nucleotide construct comprising the polynucleotide as claimed in claim
9, operably linked to a promoter; wherein the promoter is selected from a
10 group consisting of CMV promoter, EF1α promoter, chicken β-actin
promoter, SV40 promoter, Ubc promoter, and CAG promoter.
12. The nucleotide construct as claimed in claim 11, wherein the nucleotide
construct has a nucleotide sequence selected from SEQ ID NO: 25, SEQ
ID NO: 26, SEQ ID NO: 27, or SEQ ID NO : 28.
15 13. An expression vector comprising the nucleotide construct as claimed in
claim 11.
14. A host cell comprising the nucleotide construct as claimed in claim 11 or
the expression vector as claimed in claim 13.
15. The host cell as claimed in claim 14, wherein the host cell is a eukaryotic
20 cell; and the eukaryotic cell is selected from a group consisting of HEK293,
HeLa, K562, Neuro2a, U2OS, HepG2, A542, CACO2, CaOV3,
Saccharomyces cerevisiae, and Saccharomyces pombe.
16. A method of producing a fusion protein as claimed in claim 5, wherein the
method comprises:
25 a) transforming a host cell with the nucleotide construct as claimed in
claim 11 or the expression vector as claimed in claim 13 to obtain a
transformed host cell; and
b) culturing the transformed host cell under conditions favoring the
production of the fusion protein.
30 17. A method for regulating the expression of a polypeptide of interest,
wherein the method comprises:
21
a) transforming a host cell with the nucleotide construct as claimed in
claim 11 or the expression vector as claimed in claim 13;
b) culturing the transformed host cell under conditions favoring the
production of the fusion protein; and
5 c) detecting the presence or absence of a change in the expression of the
polypeptide of interest in the transformed host cell with reference to a
host cell not transformed with said nucleotide construct.