Biology subjects

Paraggio, C. L.

Publications and source records attributed to Paraggio, C. L..

3 recordsLinked to original sources

bioRxiv2026

N-glycoproteomic profiling of the hookworm Ancylostoma ceylanicum reveals heterogeneity and phosphorylcholine-modified glycans in larval and adult parasites.

Glycans of parasitic worms (helminths) have been previously described with roles in immunomodulation and the recognition of helminth proteins by the host immune system. Despite their significance in other systems, little is known about the glycosylation patterns of the hookworm Ancylostoma ceylanicum, an intestinal parasite of animals and humans, due to challenges in sample collection and structural complexity of many nematode glycans. Herein, we describe results of a released N-glycan analysis of adult hookworms, which revealed oligomannose, hybrid, and complex structures, including those with non-mammalian features. Next, we report the results of glycoproteomic analyses to identify hookworm glycoproteins and their associated glycan structures. We compared three enrichment methods and found that strong anion-exchange electrostatic repulsion liquid chromatography (SAX-ERLIC) led to the identification of the most N-glycopeptides. Analyses of larval and adult extracts revealed 82 larval and 157 adult N-glycoproteins, the majority of which were stage-specific. Of particular interest, phosphorylcholine (PC), a known immunomodulatory glycan modification, was detected in both stages, and several unique PC-modified structures were identified in each. Collectively, these results provide the first site-specific characterization of intact N-glycopeptides in A. ceylanicum and, with an adult-stage released glycan analysis, establish a method for glycoproteomic characterizations of other helminths.

microbiology↗

bioRxiv2022

Three ALS genes regulate expression of the MHC class II antigen presentation pathway

Here we report that the major histocompatibility complex II (MHC II) antigen presentation pathway is regulated by the ALS-causative genes, FUS, TAF15, or MATR3. Of >6000 proteins detected by quantitative mass spectrometry, the subunits of the MHC II heterodimer, HLA-DR, were the top 2 downregulated proteins in HeLa knock outs (KO) of these ALS genes, but not the related gene, EWSR1. Moreover, CD74, which is the 3rd essential component of HLA-DR, was downregulated in the 3 KOs. We show that the downregulations are due to loss of CIITA, a transcription factor dedicated to expression of MHC II genes. Thus, our results reveal the 1st shared cellular pathway regulated by multiple ALS genes, and this pathway is ALS genes -> CIITA -> MHC II genes. We obtained the same results in HMC3 cells, a microglia cell line, showing that loss of the MHC II pathway extends to an ALS-relevant cell type in the central nervous system (CNS). Furthermore, the MHC II pathway is downregulated in hematopoietic progenitor cells (HPCs) bearing the ALS FUSR495X mutation. This observation may be highly significant to ALS pathogenesis as HPCs give rise to a multitude of CNS-specific and systemic immune cells, both of which have known or suspected roles in ALS. Together, our data raise the possibility that loss of the MHC II pathway in a large range of immune cells results in global failure of the immune system to protect motor neurons from damage that leads to the disease. Consequently, CIITA and the other genes in the MHC II pathway may be important new therapeutic targets for the disease.

molecular biology↗

bioRxiv2022

Chemokine Receptor 1 and its associated immune pathway are downregulated in SF3B1MT blood and non-blood cancers

Mutation of the essential splicing factor SF3B1 is primarily associated with hematological cancers but also occurs in solid tumors. We edited the most common mutation, K700E, into human embryonic stem (ES) cells to determine the effects of this mutation alone in an undifferentiated/non-cancer background. Unexpectedly, >20% of the significantly upregulated genes in the SF3B1K700E ES lines have immune functions. Thus, SF3B1 may have an additional role in proper expression of immune genes in appropriate cell types. In striking contrast, we found that published RNA-seq data from SF3B1 blood (MDS, CLL, AML) and non-blood (BRCA, UVM) cancers exhibited the opposite, downregulation of a multitude of immune pathways with 7 of the pathways shared among all 5 of the SF3B1 cancers. One of these pathways, "leukocyte migration", is the 1st reported pathway shared among all splicing factor cancers, including the 5 SF3B1 cancers and MDS associated with U2AF1, SRSF2 and ZRSR2. Importantly, we identified CCR1, which is in the leukocyte migration pathway as the only shared downregulated gene in the 5 SF3B1 cancers and in U2AF1MT MDS. We conclude that downregulation of CCR1 and its associated immune pathway may play a key role in pathogenesis of these splicing factor cancers and are thus potential therapeutic targets.

molecular biology↗