Overview
| Uniprot ID | Q6ZN17 |
|---|
| Protein Name | Protein lin-28 homolog B |
|---|
| Gene Name | LIN28B |
|---|
| Organism | Homo sapiens |
|---|
Kla Sites from experimental identification
| Position |
Flanking peptide |
| 229 |
PQEASSTKSSIAPEE |
| 239 |
IAPEEQSKKGPSVQK |
| 89 |
PVEFTFKKSSKGLES |
Function
Suppressor of microRNA (miRNA) biogenesis, including that of let-7 and possibly of miR107, miR-143 and miR-200c. Binds primary let-7 transcripts (pri-let-7), including pri-let-7g and pri-let-7a-1, and sequester them in the nucleolus, away from the microprocessor complex, hence preventing their processing into mature miRNA (PubMed:22118463). Does not act on pri-miR21 (PubMed:22118463). The repression of let-7 expression is required for normal development and contributes to maintain the pluripotent state of embryonic stem cells by preventing let-7-mediated differentiation. When overexpressed, recruits ZCCHC11/TUT4 uridylyltransferase to pre-let-7 transcripts, leading to their terminal uridylation and degradation (PubMed:19703396). This activity might not be relevant in vivo, as LIN28B-mediated inhibition of let-7 miRNA maturation appears to be ZCCHC11-independent (PubMed:22118463). Interaction with target pre-miRNAs occurs via an 5'-GGAG-3' motif in the pre-miRNA terminal loop. Mediates MYC-induced let-7 repression (By similarity). When overexpressed, isoform 1 stimulates growth of the breast adenocarcinoma cell line MCF-7. Isoform 2 has no effect on cell growth
Protein Sequence
10
MAEGGASKGG
20
GEEPGKLPEP
30
AEEESQVLRG
40
TGHCKWFNVR
50
MGFGFISMIN
60
REGSPLDIPV
70
DVFVHQSKLF
80
MEGFRSLKEG
90
EPVEFTFKKS
100
SKGLESIRVT
110
GPGGSPCLGS
120
ERRPKGKTLQ
130
KRKPKGDRCY
140
NCGGLDHHAK
150
ECSLPPQPKK
160
CHYCQSIMHM
170
VANCPHKNVA
180
QPPASSQGRQ
190
EAESQPCTST
200
LPREVGGGHG
210
CTSPPFPQEA
220
RAEISERSGR
230
SPQEASSTKS
240
SIAPEEQSKK
250
GPSVQKRKKT
Gene Ontology
| Classification |
GO ID |
Description |
| Cellular Component |
GO:0005737 |
cytoplasm |
| Cellular Component |
GO:0005829 |
cytosol |
| Cellular Component |
GO:0005730 |
nucleolus |
| Cellular Component |
GO:0005654 |
nucleoplasm |
| Cellular Component |
GO:0005634 |
nucleus |
| Molecular Function |
GO:0003729 |
mRNA binding |
| Molecular Function |
GO:0003723 |
RNA binding |
| Molecular Function |
GO:1990837 |
sequence-specific double-stranded DNA binding |
| Molecular Function |
GO:0008270 |
zinc ion binding |
| Biological Process |
GO:0010587 |
miRNA catabolic process |
| Biological Process |
GO:2000632 |
negative regulation of pre-miRNA processing |
| Biological Process |
GO:2000635 |
negative regulation of primary miRNA processing |
| Biological Process |
GO:2000627 |
positive regulation of miRNA catabolic process |
| Biological Process |
GO:0031054 |
pre-miRNA processing |
| Biological Process |
GO:0031123 |
RNA 3'-end processing |
| Biological Process |
GO:0050779 |
RNA destabilization |
Reference
[1] Yang Z, Yan C, Ma J, Peng P, Ren X et al.. Lactylome analysis suggests lactylation-dependent mechanisms of metabolic adaptation in hepatocellular carcinoma.. Nat Metab 5(1):61-79. 2023 Jan. PMID: 36593272.