Project description:Hypothesis directed proteomics offers higher throughput over global analyses. We show that immunoprecipitation (IP)-tandem mass spectrometry (LC-MS/MS) in H929 multiple myeloma (MM) cancer cells led to the discovery of a rare and unexpected BCR-ABL fusion, informing a therapeutic intervention using imatinib (Gleevec). BCR-ABL is the driving mutation in chronic myeloid leukemia (CML) and is uncommon to other cancers. Three different IP-MS experiments central to cell signaling pathways were sufficient to discover a BCR-ABL fusion in H929 cells: phosphotyrosine (pY) peptide IP, p85 regulatory subunit of phosphoinositide-3-kinase (PI3K) IP, and the GRB2 adaptor IP. The pY peptides inform tyrosine kinase activity, p85 IP informs the activating adaptors and receptor tyrosine kinases (RTKs) involved in AKT activation and GRB2 IP identifies RTKs and adaptors leading to ERK activation. Integration of the bait-prey data from the three separate experiments identified the BCR-ABL protein complex, which was confirmed by biochemistry, cytogenetic methods, and DNA sequencing revealed the e14a2 fusion transcript. The tyrosine phosphatase SHP2 and the GAB2 adaptor protein, important for MAPK signaling, were common to all three IP-MS experiments. The comparative treatment of tyrosine kinase inhibitor (TKI) drugs revealed only imatinib, the standard of care in CML, was inhibitory to BCR-ABL leading to down-regulation of pERK and pS6K and inhibiting cell proliferation. These data suggest a model for directed proteomics from patient tumor samples for selecting the appropriate TKI drug(s) based on IP and LC-MS/MS. The data also suggest that MM patients, in addition to CML patients, may benefit from BCR-ABL diagnostic screening.
Project description:RNAs that are enriched in AGO2 Immunoprecipitated (IP) products or PIWIL1 IP products were identified from mouse(BALB/C) adult testes by examine the ratio of total RNA signal intensity to AGO2 IP RNA or PIWIL1 IP RNA signal intensity. Two-condition experiment,Total RNA extracted from mouse adult testes vs. AGO2 IP RNA extracted from mouse adult testes and total RNA extracted from mouse adult testes vs. PIWIL1 IP RNA extracted from mouse adult testes.
Project description:The interacting proteins of HNRNPF were identified in mouse embryonic stem cells by co-immunoprecipitation followed by mass spectrometry (Co-IP/MS).
Project description:Despite KAT6A chimeras potent oncogenic activity, the mechanisms by which KAT6A fusion proteins achieve genomic specificity and drive leukemogenesis remain poorly understood. Previous studies suggest that the leukemogenic potential of KAT6A-TIF2 depends on its chromatin-binding ability rather than its histone acetyltransferase (HAT) activity, with oncogenicity further amplified by CBP recruitment through its fusion partners. The winged helix domain (WH1) of KAT6A can bind unmethylated CpG islands and interact with P300/CBP via the TAZ2 domain. However, the widespread presence of unmethylated CpG islands across the genome does not fully explain the genomic specificity of KAT6A-CBP (K/C) and KAT6A-P300 (K/P) fusions, leaving key mechanistic gaps unexplored. To uncover protein interactions underlying these genomic associations, we performed immunoprecipitation and mass spectrometry (IP-MS) on KAT6A N-terminus and chimeras. Mass spectrometry analysis was performed to identify the core components of the KAT6A complex and the interacting proteins of KAT6A.
Project description:We report the RNA-seq data of Klf2 knockdowned cells and Snd1 knockdowned cells from mouse embryonic stem cells. Samples were lysed with total RNA prep kit.
Project description:RNAs that are enriched in AGO2 Immunoprecipitated (IP) products or PIWIL1 IP products were identified from mouse(BALB/C) adult testes by examine the ratio of total RNA signal intensity to AGO2 IP RNA or PIWIL1 IP RNA signal intensity.
Project description:Snake envenomation poses a significant risk to Malaysians and country visitors. Malaysia witnesses an estimated 650 snake bites per 100,000 population annually. The primary treatment for snake envenomation involves administering antivenom derived from horses, despite its drawbacks, such as anaphylactic reactions and serum sickness. Identifying the venom proteome is crucial for understanding and predicting the clinical implications of envenomation and developing effective treatments targeting specific venom proteins. In this study, we employ an immunoprecipitation assay followed by LC-MS/MS to identify antigenic proteins in five common venomous snakes in Malaysia compassing of two families which are pit vipers, (Calloselasma rhodostoma and Cryptelytrops purpureomaculatus) and cobras (Ophiophagus hannah, Naja kaouthia, and Naja sumatrana). The immunoprecipitation assay utilises a 2 % agarose gel, allowing antigenic proteins to diffuse and bind with antibodies in the antivenom. The antivenom utilised in this research was procured from the Queen Saovabha Memorial Institute (QSMI), Thailand, including king cobra antivenom (KCAV), cobra antivenom (CAV), Malayan pit viper antivenom (MPAV), Russell's viper antivenom (RPAV), hematopolyvalent antivenom (HPAV), neuropolyvalent antivenom (NPAV), banded krait antivenom (BKAV), and Malayan krait antivenom (MKAV). The protein identified through these interactions which are exclusive to the cobras are three-finger toxins (3FTXs) while snake C-type lectins (Snaclecs) are unique to the pit vipers. Common protein that are present in both families are L-amino acid oxidase (LAAO), Phospholipase A2 (PLA2), and snake venom metalloproteinase (SVMP). Identifying these proteins is vital for formulating a broad-spectrum antivenom applicable across multiple species.
Project description:We deep-sequenced small RNAs after immunoprecipitation of Mili or Miwi, as well as total small RNA from adult mouse testis. The goal of this experiment is to more deeply characterize the piRNA pool from adult mouse testes, using the Illumina platform. Comparison of 2 IP libraries with a non-IP library
Project description:Methanococcus maripaludis is a methanogenic archaeon. Within its genome, there are two operons for membrane associated hydrogenases, eha and ehb. To investigate the regulation of ehb on the cell, an S40 mutant was constructed in such a way that a portion of the ehb operon was replaced by pac cassette in the wild type parental strain S2 (done by Whitman's group at the University of Georgia). The S40 and S2 strains were grown in 14N and 15N media with acetate separately. A biological replicate was made by switching the media. Mass spectrometry based quantitative proteomics were done on the mixtures to investigate the differences in expression patterns between S40 and S2. Keywords: isotope labeling mass spectrometry, quantitative proteomics