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[
2016]
Chromatin diminution is defined as chromosomal fragmentation, followed by the elimination of part of the chromosome during mitosis. The process was first observed in early cleavage divisions of the parasitic nematode Parascaris equorum embryo by Boveri in 1887. It was later found to also occur in some other parasitic nematodes, as well as a number of unicellular and metazoan species in diverse taxonomic groups. While chromatin diminution occurs in diverse higher order taxa, within individual taxa, it occurs only in a rather small number of species. The process appears to play different biological roles in different organisms, may use different mechanisms and is likely to have arisen multiple times during evolution.
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[
Parasitol Today,
1996]
Spliced leader trans-splicing is a form of RNA processing originally described and studied in parasitic kinetoplastida. This mechanism of gene expression also occurs in parasitic and free-living metazoa. In this review, Dick Davis describes current knowledge of the distribution, substrates, specificity and functional significance of trans-splicing in metazoa.
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[
Autophagy,
2024]
Professor Richard (Rick) Morimoto is the Bill and Gayle Cook Professor of Biology and Director of the Rice Institute for Biomedical Research at Northwestern University. He has made foundational contributions to our understanding of how cells respond to various stresses, and the role played in those responses by chaperones. Working across a variety of experimental models, from <i>C</i>. <i>elegans</i> to human neuronal cells, he has identified a number of important molecular components that sense and respond to stress, and he has dissected how stress alters cellular and organismal physiology. Together with colleagues, Professor Morimoto has coined the term "proteostasis" to signify the homeostatic control of protein expression and function, and in recent years he has been one of the leaders of a consortium trying to understand proteostasis in healthy and disease states. I took the opportunity to talk with Professor Morimoto about proteostasis in general, the aims of the consortium, and how autophagy is playing an important role in their research effort.
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[
Exp Gerontol,
2006]
In Caenorhabditis elegans, the insulin/IGF-1 signaling pathway controls many biological processes such as life span, fat storage, dauer diapause, reproduction and stress response . This pathway is comprised of many genes including the insulin/IGF-1 receptor (DAF-2) that signals through a conserved PI 3-kinase/AKT pathway and ultimately down-regulates DAF-16, a forkhead transcription factor (FOXO). DAF-16 also receives input from several other pathways that regulate life span such as the germline and the JNK pathway [Hsin, H., Kenyon, C., 1999. Signals from the reproductive system regulate the lifespan of C. elegans. Nature 399, 362-366; Oh, S.W., Mukhopadhyay, A., Svrzikapa, N., Jiang, F., Davis, R.J., Tissenbaum, H.A., 2005. JNK regulates lifespan in Caenorhabditis elegans by modulating nuclear translocation of forkhead transcription factor/DAF-16. Proc. Natl. Acad. Sci. USA 102, 4494-4499]. Therefore, DAF-16 integrates signals from multiple pathways and regulates its downstream target genes to control diverse processes. Here, we discuss the signals to and from DAF-16, with a focus on life span regulation.
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[
Methods Cell Biol,
1995]
ACeDB (A Caenorhabditis elegans Data Base) is a data management and display system that contains a wide range of genomic and other information about C. elegans. This chapter provides an overview of ACeDB for the C. elegans user, focusing in particular on the Macintosh version Macace. Previous reviews of AceDB include those of Thierry-Mieg and Durbin (1992) and Durbin and Thierry-Mieg (1994), which describe the general properties of the whole system, and that by Dunham et al. (1994), which discussed the use of AceDB for physical map data collection and assembly. ACeDB was developed by Jean Thierry-Mieg and Richard Durbin primarily for the C. elegans project, when the genomic sequencing project was just beginning in 1990. The original aim was to create a single database that integrated the genetic and physical maps with both genomic sequence data and the literature references. The forerunner of ACeDB was the program CONTIG9 (Sulston et al., 1988), which was developed to maintain and edit the physical map. CONTIG9 served researchers around the world by providing critical on-line access to the current physical map as it was being constructed (Coulson et al., 1986). This policy of immediate access allowed members of the worm community to see the same data as the people making the map, and proved very successful in maximizing use of the map. The same approach was adopted as a template for ACeDB. These two principles, developing a comprehensive database for all types of genomic and related data and providing public access to the data in the same form as used by the data-collecting laboratories, have continued to underlie developments of ACeDB. Over the last 5 years, a wide range of genome projects relating to other organisms have taken the ACeDB program and used it to develop databases for their own data. ACeDB has been used both in public projects designed to redistribute public data in a coordinated fashion and laboratory-based projects for collecting new data. Others, such as the C. elegans ACeDB, have used the database for both purposes. The reason it has been possible to adapt ACeDB so widely is that its flexible data structure allows new types of objects and new types of information about these objects to be added easily. This chapter describes (1) how to obtain ACeDB and documentation for it, (2) how to access and use the information in ACeDB, and (3) how to use ACeDB as a laboratory-based data managing system. Some of what we discuss is specific to the nematode database, but other information applies to the basic computer software program and, hence, to any database using the ACeDB program.