Cryptosporidium parvum: effect of multi-drug reversing agents on the expression and function of ATP-binding cassette transporters

Bonafonte, Marı́a-Teresa; Romagnoli, Pablo A.; McNair, Nina; Shaw, Andrew; Scanlon, Mary; Leitch, Gordon J.; Mead, Jan R.

doi:10.1016/j.exppara.2004.03.012

Cited by 19 publications

(15 citation statements)

References 29 publications

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“…A C. parvum in vitro assay was carried out as described previously (Bonafonte et al 2004). Briefly, plates containing confluent HCT-8 cells were infected with a mixture of C. parvum oocysts and sporozoites.…”

Section: Resultsmentioning

confidence: 99%

“…RNA was isolated from infected cultures, and quantitative real-time RT-PCR analysis was performed to observe modulation of transcript levels for each ABC transporter. Relative quantitation of gene expression was carried out using the comparative C T method, and the relative target expression C T value was normalized against the C. parvum ssRNA housekeeping gene, as it is expressed constitutively regardless of time post-infection or treatment conditions (Bonafonte et al 2004). To confirm accuracy and reproducibility of RT-PCR, the intra-assay precision was determined in duplicate within one experiment.…”

Section: Resultsmentioning

confidence: 99%

“…Some of these factors may include its complex life cycle and differences in targets at the molecular, structural levels or in biochemical pathways. Two other contributing factors include (1) the parasite's unique location in the host cell (intracellular but extracytoplasmic), which may act as a barrier making it difficult for drugs to reach their target and (2) the presence of transport proteins or efflux pumps that transport drugs out of the parasite (Bonafonte et al 2004).…”

Section: Introductionmentioning

confidence: 99%

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Modulation of gene expression of three Cryptosporidium parvum ATP-binding cassette transporters in response to drug treatment

2007

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We studied three ATP-binding cassette (ABC) transporters (cgd1_1350, cgd7_4510, and cgd7_4520) of Cryptosporidium parvum that were identified to share a high level of homology with nucleotide binding domains of other parasitic ABC transporters and therefore could be potential candidates of efflux of drugs and/or contribute to the intrinsic resistance to chemotherapy observed of this parasite. Partial characterization and expression analysis of three C. parvum ABC transporters was determined by standard semi-quantitative real-time polymerase chain reaction. Expression of mRNA of the three ABC transporters was detected at different time points in infected cell cultures over the 48-h period, corresponding to the development of the sexual and asexual stages of the parasite. To determine if these three transporters were modulated in response to drug treatment, infected HCT 8 cells were then incubated for 48 h with different concentrations of paromomycin and a single concentration of cyclosporin A. Our results indicated that treatment by paromomycin resulted in approximately five to eightfold upregulation of cgd1_1350 transcript and about threefold of upregulation of Cgd7_4510 transcript levels. Cyclosporin A had a similar upregulating effect on cgd1_1350 and cgd7_4510 RNA levels: fivefold and 2.6-fold, respectively. On the contrary, drug treatment had little effect on cgd7_4520 transcript levels. Therefore, two of these transporters may be of value as tools for the study and the rational drug design of specific inhibitors to counteract C. parvum's intrinsic drug resistance.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Modulation of gene expression of three Cryptosporidium parvum ATP-binding cassette transporters in response to drug treatment

2007

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“…CpABCC4 shows similarity to human CFTR and MRP-like protein from Candida albicans and has been identified in the apical end of sporozoites (Zapata et al 2002). Gene expression of CpABCB1, an ABC transporter with similarity to MDR1, was detected in intracellular stages of C. parvum but its localization is unknown (Bonafonte et al 2004;Zapata et al 2002). These transporters are constitutively expressed in infected cell cultures, with transcript levels of CpABCC3 4 logs higher than either CpABCB1 or CpABCC4.…”

Section: Abc and Other Parasite Transportersmentioning

confidence: 96%

“…These transporters are constitutively expressed in infected cell cultures, with transcript levels of CpABCC3 4 logs higher than either CpABCB1 or CpABCC4. In addition, MDR or MRP modulators (cyclosporine A, verapamil and probenicid) significantly affected transcript levels of all three of these ABC transporters in C. parvum (Bonafonte et al 2004) and several sesquiterpenes have been shown to bind to the recombinant nucleotide-binding site of an MDR-like efflux pump when assayed on the recombinant nucleotide-binding domain of CpABCB1 (Lawton et al 2007). While classic drug resistance has not been demonstrated with any of these ABC proteins, treatment by paromomycin, one of the most widely used agents to treat cryptosporidial infections in AIDS patients, significantly upregulates transcription of CpABCC14 (cgd7_4510) and of the CpABCB4 (cgd1_1350 or CpABC4 or CpATM1) (Benitez et al 2007), a Pgp homolog half transporter.…”

Section: Abc and Other Parasite Transportersmentioning

confidence: 97%

Treatment of Cryptosporidiosis

Mead

Arrowood

2013

Cryptosporidium: Parasite and Disease

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Cryptosporidium species are protozoan parasites that infect the epithelial cells of the gastrointestinal tract. In humans, infections occur primarily in the small intestine resulting in diarrheal illness. Cryptosporidium has a worldwide distribution and is considered an emerging zoonosis. Despite intensive efforts to develop workable experimental models, and the evaluation of nearly 1,000 chemotherapeutic agents, adequate therapies to clear the host of these parasites are still lacking. The reasons for the lack of drug efficacy are probably manifold and may include the unusual location of the parasite in the host cell, distinct structural and biochemical composition of drug targets, or its ability to either block import or rapidly efflux drug molecules. Understanding the basic mechanisms by which drugs are transported to the parasite and identifying unique targets are important steps in developing effective therapeutic agents.

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Histone acetylation is associated with pupal diapause in cotton bollworm, Helicoverpa armigera

Lu,

Li,

Liao

et al. 2023

Pest Management Science

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BACKGROUNDDiapause is an environmentally preprogrammed period of arrested development that is important to insect survival and population growth. Histone acetylation, an epigenetic modification, has several biological functions, but its role in agricultural pest diapause is unknown. In this study, we investigated the role of histone H3 acetylation in the diapause of Helicoverpa armigera.RESULTSThe histone H3 gene of H. armigera was cloned, and multiple sequence alignment of amino acids revealed that the potential lysine acetylation sites were highly conserved across species. Investigation of histone H3 acetylation levels in diapause‐ and nondiapause‐type pupae showed that acetylation levels were down‐regulated in diapause‐type pupae and were lower in diapausing pupae compared to nondiapause pupae. By screening the genome, six histone acetyltransferase (HAT) and eight histone deacetylase (HDAC) genes responsible for antagonizing catalytic histone acetylation modifications were identified in H. armigera, and most of them exhibited different expression patterns between diapause‐ and nondiapause‐type pupae. To elucidate the effect of histone H3 acetylation on diapause in H. armigera, the diapause pupae were injected with the histone acetylation activator trichostatin A (TSA). The results indicated that TSA injection increased the levels of histone H3 acetylation, causing the diapausing pupae to revert to development. Furthermore, transcriptome analysis revealed that 259 genes were affected by TSA injection, including genes associated with metabolism, resistance, and immunological responses.CONCLUSIONThese results suggest that histone acetylation is inseparably related to the pupal diapause of H. armigera, which promises to be a potential target for pest control. © 2023 Society of Chemical Industry.

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Cryptosporidium parvum: effect of multi-drug reversing agents on the expression and function of ATP-binding cassette transporters

Cited by 19 publications

References 29 publications

Modulation of gene expression of three Cryptosporidium parvum ATP-binding cassette transporters in response to drug treatment

Modulation of gene expression of three Cryptosporidium parvum ATP-binding cassette transporters in response to drug treatment

Treatment of Cryptosporidiosis

Histone acetylation is associated with pupal diapause in cotton bollworm, Helicoverpa armigera

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