Transmission electron microscopy was used to study the ultrastructural changes induced by exposure to Cd or Zn in three species of ciliated protozoa: Colpoda steinii, Cyrtolophosis elongata and Drepanomonas revoluta. The main cytoplasmic alterations were partial mitochondrial degeneration, cytoplasmic vacuolisation, accumulation of membranous debris and autophagosome formation. At the nuclear level we detected nucleolar fusion in the macronucleus, and micronuclear membrane modifications. We compared these modifications with those coinciding with ciliate encystment (a differentiation process induced by environmental nutritional stress) and with changes in eukaryotic cells treated with staurosporine, a potent protein kinase inhibitor considered to be an apoptosis inducer. Exposure to heavy metals also coincided with the appearance of electron-dense accumulations in the cytoplasm, which might be related to metallothionein-mediated detoxification. The results are compared with previously reported data from ciliates and microalgae treated with heavy metals.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cellbi.2004.09.010 | DOI Listing |
Ying Yong Sheng Tai Xue Bao
October 2024
Liaoning Ocean and Fisheries Science Research Institute/Key Laboratory of Protection and Utilization of Aquatic Germplasm Resource, Ministry of Agriculture and Rural Affairs/Key Laboratory of Molecular Biology for Marine Fishery, Dalian 116023, Liaoning, China.
We investigated food composition and feeding selectivity of jellyfish () from the coastal aquaculture ponds in Liaodong Bay by DNA metabarcoding technology. The DNA from environmental water samples and stomach contents of were extracted and sequenced by high-throughput sequencing with 18S rDNA V4 region and mitochondrial cytochrome c oxidase subunit I (COI) as metabarcoding markers. Based on 18S rDNA metabarcoding, we detected 27 phyla in the stomach contents of , in which Mollusc was the dominant phylum followed by Arthropod, and 34 phyla in the environmental water samples, in which Pyrrophyta was the dominant phylum followed by Ciliophora and Ascomycota.
View Article and Find Full Text PDFPLoS Genet
December 2024
Earlham Institute, Norwich Research Park, Norwich, United Kingdom.
The translation of nucleotide sequences into amino acid sequences, governed by the genetic code, is one of the most conserved features of molecular biology. The standard genetic code, which uses 61 sense codons to encode one of the 20 standard amino acids and 3 stop codons (UAA, UAG, and UGA) to terminate translation, is used by most extant organisms. The protistan phylum Ciliophora (the 'ciliates') are the most prominent exception to this norm, exhibiting the grfeatest diversity of nuclear genetic code variants and evidence of repeated changes in the code.
View Article and Find Full Text PDFSci Total Environ
December 2024
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Environment, Beijing Normal University, Beijing 100080, China.
Unraveling how microeukaryotic generalists and specialists assemble and coexist under environmental stress is central to our understanding of the mechanisms maintaining diversity. Here, we explored the biogeographical distributions of microeukaryotic generalists and specialists in lake surface sediments along a salinity gradient on the Qinghai-Tibet Plateau. We found that relative abundances of Chlorophyta (28.
View Article and Find Full Text PDFJ Postgrad Med
October 2024
Department of Microbiology, Mahatma Gandhi University of Medical Sciences and Technology, Jaipur, Rajasthan, India.
Balantidium coli is the largest, uncommon, and only ciliate parasite that infects humans and is more common in tropics and subtropical regions. It is mostly asymptomatic, but can cause diarrhea and abdominal pain and sometimes leads to perforation of the colon. It is harbored in animals, particularly among pigs in hotter environments and monkeys in the jungles.
View Article and Find Full Text PDFZootaxa
May 2024
Laboratório de Protozoologia; Programa de Pós-graduação em Biodiversidade e Conservação da Natureza; Universidade Federal de Juiz de Fora; CEP: 36036-900; Juiz de Fora; Minas Gerais; Brazil.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!