title: Enhanced membrane-tethered mucin 3 (MUC3) expression by a tetrameric branched peptide with a conserved TFLK motif inhibits bacteria adherence.
abstract: We investigated whether a synthetic tetrameric branched peptide based on the conserved TFLK motif from mammary-associated serum amyloid A3 (M-SAA3) is more efficient than the monomeric peptide at up-regulating MUC3 expression and examined the possible mechanism(s) and biological significance of this process. We used standard solid-phase methods to synthesize a tetrameric branched peptide (sequence GWLTFLKAAG) containing a trilysine core, termed the TFLK-containing 10-mer BP. The aberrant expression of transcription factors was analyzed using a transcription factor protein/DNA array. MUC3 and relevant transcription factors were detected using real-time PCR and/or Western blots. The luciferase assay, EMSA, and ChIP assays were used to analyze the activity of the human MUC3 promoter. The bacterial adherence assay was used to evaluate the in vitro inhibition of enteropathogenic Escherichia coli or enterohemorrhage E. coli serotype O157:H7 (EHEC O157:H7) adherence to HT-29-Gal cells after treatment with the TFLK-containing 10-mer BP. In HT-29-Gal cells, the TFLK-containing 10-mer BP induced higher levels of MUC3 expression than the M-SAA3-derived N-terminal 10-mer monomeric peptide, and MUC3 expression was activated through transcriptional mechanisms, including the induction of multiple transcription factors and further binding with their cis-elements between nucleotides -242 and -62 within MUC3 promoter. Interestingly, the TFLK-containing 10-mer BP dramatically inhibited enteropathogenic E. coli and EHEC O157:H7 adherence to the HT-29-Gal cells compared with the controls. This finding suggests a potential therapeutic use for this peptide to prevent gastrointestinal infection.
authors: Department of Gastroenterology, Southwest Hospital, Chongqing, 400038 China.
authors: Qiong
authors: Q
authors: Pan
authors: Yin
authors: Y
authors: Tian
authors: Xiaohuan
authors: X
authors: Li
authors: Jun
authors: J
authors: Ye
authors: Yun
authors: Y
authors: Liu
authors: Lili
authors: L
authors: Song
authors: Yongtao
authors: Y
authors: Yang
authors: Rong
authors: R
authors: Zhu
authors: Yonghong
authors: Y
authors: He
authors: Lei
authors: L
authors: Chen
authors: Wensheng
authors: W
authors: Chen
authors: Xuhu
authors: X
authors: Mao
authors: Zhihong
authors: Z
authors: Peng
authors: Rongquan
authors: R
authors: Wang
mesh_terms: D020816:Amino Acid Motifs; D001422:Bacterial Adhesion; D004926:Escherichia coli / Q000378:metabolism; D019453:Escherichia coli O157 / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000382:microbiology; D005786:Gene Expression Regulation; D019073:HT29 Cells; D006801:Humans; D008957:Models, Genetic; D055263:Mucin-3 / Q000096:biosynthesis* / Q000502:physiology*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010455:Peptides / Q000737:chemistry*; D011401:Promoter Regions, Genetic; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D014158:Transcription, Genetic
chemical_list: C524652:MUC3A protein, human; D055263:Mucin-3; D010455:Peptides