Stem cell biology
Christine Hauskeller, Arne Manzeschke, Anja Pichl in The Matrix of Stem Cell Research, 2019
As presented above, stem cells are defined in the first instance in terms of cellular entities, characters, and processes. But, on closer inspection, whole multicellular organisms are implicated in the definition as well. Most obviously, stem cells are derived from an organismal source. Every stem cell is a part of, or is descended via cell division from a part of, exactly one multicellular organism. The scientific names of major stem cell varieties often refer to features of the source organism – notably, species and developmental stage. For example, ‘hESC’ is an abbreviation of ‘human embryonic stem cell’, ‘m-epiSC’ of ‘mouse epiblast stem cell’. Stem cells found within a mature organism (‘adult stem cells’) are named for the part of that organism they build and/or replenish: neural stem cells, hematopoietic stem cells, epithelial stem cells, muscle stem cells, etc. More broadly, stem cell research has long been divided into two branches, which focus on ‘adult’ or ‘embryonic’ stem cells, respectively. The adult/embryonic distinction refers to the developmental stage of stem cells’ organismal source.
Marine Algal Secondary Metabolites Are a Potential Pharmaceutical Resource for Human Society Developments
Se-Kwon Kim in Marine Biochemistry, 2023
Marine macroalgae, otherwise known as seaweeds, are mostly found in the tropical waters and intertidal regions. These macroalgae are multicellular organisms. They differ in their morphological types and sizes. They are classified based on their photosynthetic pigments into red, green, and brown algae. Recently, over 3,200 products have been isolated from marine macroalgae. The compounds that have derived from the marine macroalgae, have been useful in the field of medicine such as antioxidant, anticoagulant, antitumor, antifouling, antibacterial, antifungal, etc., also it is stated that the red seaweeds are used in the treatments of diarrhea and gastritis (Table 15.3). Not only that, green and brown seaweeds have been used in the various treatments of diseases such as rheumatic diseases, skin diseases, gastric ulcers, goiter, etc.
Understanding Aging after Darwin
Shamim I. Ahmad in Aging: Exploring a Complex Phenomenon, 2017
The basis of this theory was outlined by Kirkwood in 1977. Kirkwood pointed out that errors in the synthesis of proteins which performed vital cellular functions would have serious consequences for organismal fitness. If the occurrence of errors in protein synthesis was an ongoing phenomenon, the result would be the accumulation of defective proteins and ultimately death of the organism. To avoid such a situation, mechanisms would have to be in place to detect and correct errors which occurred during protein synthesis. Kirkwood (1977) drew a distinction between unicellular and multicellular organisms. He only considered aging of multicellular organisms since they had distinct germline and somatic cells. Germline transmits information to succeeding generations but somatic cells do not. Since accuracy in germline protein synthesis was critical for successful reproductive function and given the finite resources of the organism, more of these resources would be invested into error regulation and repair in germline and less into error regulation and repair in somatic cells. Aging resulted from the progressive accumulation of defective proteins in somatic cells and this accumulation would be greater post reproductively when the force of selection was weaker.
Foodomics for human health: current status and perspectives
Published in Expert Review of Proteomics, 2018
Daniela Braconi, Giulia Bernardini, Lia Millucci, Annalisa Santucci
Genomic information and environment may actually not provide sufficient data to foresee the typical phenotypic outcome of an individual [117]. In fact, multicellular organisms do not exist as independent entities; rather they host millions of commensals, symbiotic, and pathogenic microorganisms (constituting the ‘microbiota’) and are viewed as ‘superorganisms’ [118]. The presence of such a complex ecosystem dynamically interacting with diet and the host [117] has critical relapses in terms of health and diseases, playing a fundamental role in essential physiological processes such as immunity and metabolism [119,120]. A high interindividual heterogeneity resulting from different genetic background, lifestyle, and environment further hinders the understanding of such a complex system [120].
Copper oxide nanoparticles promote the evolution of multicellularity in yeast
Published in Nanotoxicology, 2019
Jiaqi Tan, Qixin He, Jennifer T. Pentz, Cheng Peng, Xian Yang, Meng-Hsiu Tsai, Yongsheng Chen, William C. Ratcliff, Lin Jiang
The origin of multicellular organisms from unicellular ancestors is considered a major transition in evolution (Maynard Smith and Szathmary 1999), paving the way for further development in organismal complexity. The first step in the transition to multicellularity is the formation of undifferentiated groups. Also, as a unique life history strategy for microorganisms, undifferentiated multicellularity can provide advantages to microbes in harsh environments by reducing surface-to-volume ratios (Smukalla et al. 2008) and promoting resource utilization efficiency (Pfeiffer and Bonhoeffer 2003; Koschwanez, Foster, and Murray 2011). These benefits, however, may be outweighed by the costs of social conflicts (Hamilton 1964), such as the decrease in growth (Ratcliff et al. 2012). Overall, the ecological mechanisms underlying the establishment and maintenance of multicellularity in microorganisms remain poorly understood. We experimentally investigated how CuO NP exposure influences the evolution of multicellularity in Baker’s yeast (Saccharomyces cerevisiae Y55). Starting with a unicellular ancestor, we provided an evolutionary incentive for the yeast to form groups by performing daily gravitational selection. Against the backdrop of physical selection for group formation, we compared the evolutionary trajectories of yeast under exposure to CuO NPs, copper ions, or CuO bulk particles for 42 days (∼280 generations).
Overview of gene expression techniques with an emphasis on vitamin D related studies
Published in Current Medical Research and Opinion, 2023
Jeffrey Justin Margret, Sushil K. Jain
During cell development, certain sets of genes express proteins that allow them to communicate with neighboring cells to coordinate development in multicellular organisms. All living organisms make use of this process, known as gene expression, to create the building blocks of life from genetic information1. The exceedingly complex process of gene expression enables cells to control their size, shape, and functions as it involves the interactions among DNA, RNA, and proteins, as well as with the environment. The phenotype of an organism is determined by how its genes are expressed2 and regulated at many levels. The protein expressed determines the function of the cell, and each cell type has a unique gene expression profile. Thus, gene expression profiling is a fundamental tool with which to investigate changes in the expression at a cellular level, thus unraveling the complexity of biological systems and the effects of mutations that result in disease states or pathobiology.