ding, x. | bioRxiv Science

bioRxiv2021

OaAEP1-mediated PNA-protein conjugation enables erasable imaging of membrane protein

Methods to efficiently and site-specifically conjugate proteins to nucleic acids could enable exciting application in bioanalytics and biotechnology. Here, we report the use of the strict protein ligase to covalently ligate a protein to a peptide nucleic acid (PNA). The rapid ligation requires only a short N-terminal GL dipeptide in target protein and a C-terminal NGL tripeptide in PNA. We demonstrate the versatility of this approach by conjugating three different types of proteins with a PNA strand. The biostable PNA strand then serves as a generic landing platform for nucleic acid hybridization. Lastly, we show the erasable imaging of EGFR on HEK293 cell membrane through toehold-mediated strand displacement. This work provides a controlled tool for precise conjugation of proteins with nucleic acids through an extremely small peptide linker and facilitates further study of membrane proteins. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=56 SRC="FIGDIR/small/467647v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@a8e3adorg.highwire.dtl.DTLVardef@1fba15borg.highwire.dtl.DTLVardef@11e606eorg.highwire.dtl.DTLVardef@14cfc49_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

bioRxiv2019

A novel statistical method to mining the suspicious lethal genes and mutation sites by abnormal distributions of SNP patterns

A gene, a locatable region of genomic sequence, is the basic functional unit of heredity. Differences in genes lead to the various congenital physical conditions of people. One kind of these major differences are caused by genetic variations named single nucleotide polymorphisms(SNPs). SNPs may affect splice sites, protein structures and so on, and then cause gene abnormities. Some abnormities will lead to fatal diseases. People with these diseases have a small probability of having children. Thus the distributions of SNP patterns on these sites will be different with distributions on other sites. Based on this idea, we present a novel statistical method to detect the abnormal distributions of SNP patterns and then to locate the suspicious lethal genes. We did the test on HapMap data and found 74 suspicious SNPs. Among them, 10 SNPs can map reviewed genes in NCBI database. 5 genes out of them relate to fatal children diseases or embryonic development, 1 gene can cause spermatogenic failure, the other 4 genes are also associated with many genetic diseases. The results validate our idea. The method is very simple and is guaranteed by a statistical test. It is a cheap way to discover the suspicious pathogenic genes and the mutation site. The mined genes deserve further study. Author summaryXiaojun Ding received the BS, MS and PhD degrees in computer science from Central South University. Now he is a assistant professor in Yulin Normal University. His research interests include computational biology and machine learning.

bioinformatics↗