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Physiol Genomics,
2003]
Life developed in a stressful environment. Stressors at the cellular level include heat, hypoxia, oxidative or reductive substances, mechanical or osmotic pressure, and toxic compounds like heavy metals. Various molecular pathways, more or less specific for the different stressors, developed during evolution to combat the molecular consequences of cell stress. Thermal stress induces the induction of a highly conserved protein family, the heat shock proteins (HSP).
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Nutrition,
1998]
A recent flurry of activity has signaled the maturing of molecular gerontology. During the 1970s and 1980s, while many complex biological processes were being described and explained at the molecular level, the science of aging seemed to lag somewhat behind. Although the complexityof aging processes remains daunting to the experimentalist, research on aging is on the increase and the molecular processes which determine organismal lifespan are emerging.
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Genetics,
2015]
A little over 50 years ago, Sydney Brenner had the foresight to develop the nematode (round worm) Caenorhabditis elegans as a genetic model for understanding questions of developmental biology and neurobiology. Over time, research on C. elegans has expanded to explore a wealth of diverse areas in modern biology including studies of the basic functions and interactions of eukaryotic cells, host-parasite interactions, and evolution. C. elegans has also become an important organism in which to study processes that go awry in human diseases. This primer introduces the organism and the many features that make it an outstanding experimental system, including its small size, rapid life cycle, transparency, and well-annotated genome. We survey the basic anatomical features, common technical approaches, and important discoveries in C. elegans research. Key to studying C. elegans has been the ability to address biological problems genetically, using both forward and reverse genetics, both at the level of the entire organism and at the level of the single, identified cell. These possibilities make C. elegans useful not only in research laboratories, but also in the classroom where it can be used to excite students who actually can see what is happening inside live cells and tissues.
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Curr Opin Genet Dev,
1996]
This issue of Current Opinion in Genetics and Development examines mechanisms by which pattern is established during the development of a broad range of organisms and in a wide variety of tissues. Perhaps the most important message to emerge is that, on the whole, developmental mechanisms have been extraordinarily well conserved during evolution. Each embryo appears to have at its disposal a fundamental 'toolkit' of regulators and regulatory pathways with which to construct an organism. Most chapters in this issue discuss the tools; the last chapter, by contrast, addresses the evolutionary question of how different embryos give rise to distinct organisms with essentially the same 'tool-kit' of molecules during development.
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FEBS J,
2023]
Developmental programs are tightly regulated networks of molecular and cellular signaling pathways that orchestrate the formation and organization of tissues and organs during organismal development. However, these programs can be disrupted or activated in an untimely manner, or in the wrong tissues, and this can lead to a host of diseases. This aberrant re-activation can occur due to a multitude of factors, including genetic mutations, environmental influences, or epigenetic modifications. Consequently, cells may undergo abnormal growth, differentiation, or migration, leading to structural abnormalities or functional impairments at the tissue or organismal level. This Subject Collection of The FEBS Journal on Developmental Pathways in Disease highlights 11 reviews and three research articles that cover a broad array of topics focused on the role of signaling pathways critical for normal development that are deregulated in human disease.
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Am J Trop Med Hyg,
2016]
Onchocerciasis is one of the two filarial helminth "neglected tropical diseases" (the other being lymphatic filariasis) that has been targeted for geographically local elimination followed by global eradication. The last known areas of Onchocerca volvulus transmission in the Americas have recently been reported to be eliminated. In contrast, achieving metrics for interruption of O. volvulus transmission in Africa, thus removing the requirement for continued monitoring and mass drug administration (MDA) with ivermectin, has been more challenging. To date, transmission cessation of O. volvulus has been validated only in the Mount Elgon region of eastern Uganda. Annual and biannual ivermectin MDA was delivered in this endemic focus from 1994 to 2011, in combination with sustained vector control aimed at reducing the local larval Simulium neavei vectors that have a phoretic association with freshwater crabs. Subsequent to this accomplishment, the World Health Organization (WHO) updated in 2016 the criteria for stopping MDA as a result of transmission interruption. The technical procedures and the corresponding cutoff values to signify transmission interruption included the following: 1) screening pools of black flies by polymerase chain reaction for the DNA repeat sequence Ov150; minimal elimination value is < 1/2,000 Ov150-positive flies and 2) serologic screening of school-aged children < 10 years of age for immunoglobulin G4 antibodies to the Ov16 antigen; elimination value is antibody prevalence < 0.1%. In this issue of the American Journal of Tropical Medicine and Hygiene, Zarroug and others describe results of a 3-year post-MDA treatment survey that confirm elimination of O. volvulus transmission by these criteria in Abu Hamed, a geographically isolated endemic focus in northern Sudan inhabited by approximately 120,000 people. Of the 5,266 children tested for Ov16 antibody, one 9-year-old child was positive. This child had never traveled outside her home village and had a negative skin snip for Ov150 DNA, indicating that she probably did not have a patent infection with skin microfilariae, but had previously been exposed to O. volvulus infective larvae. Lymphatic filariasis or other parasitic worm infections that may elicit antibodies that cross-react with Ov16 are not endemic in the study area.