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Heterologous
The term heterologous has several meanings in biology. Gene expression In cell biology and protein biochemistry, heterologous expression means that a protein is experimentally put into a cell that does not normally make (i.e., express) that protein. Heterologous (meaning 'derived from a different organism') refers to the fact that often the transferred protein was initially cloned from or derived from a different cell type or a different species from the recipient. Typically the protein itself is not transferred, but instead the 'correctly edited' genetic material coding for the protein (the complementary DNA or cDNA) is added to the recipient cell. The genetic material that is transferred typically must be within a format that encourages the recipient cell to express the cDNA as a protein (i.e., it is put in an expression vector). Methods for transferring foreign genetic material into a recipient cell include transfection and transduction. The choice of recipient cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterogeneous
Homogeneity and heterogeneity are concepts relating to the uniformity of a substance, process or image. A homogeneous feature is uniform in composition or character (i.e., color, shape, size, weight, height, distribution, texture, language, income, disease, temperature, radioactivity, architectural design, etc.); one that is heterogeneous is distinctly nonuniform in at least one of these qualities. Etymology and spelling The words ''homogeneous'' and ''heterogeneous'' come from Medieval Latin ''homogeneus'' and ''heterogeneus'', from Ancient Greek ὁμογενής (''homogenēs'') and ἑτερογενής (''heterogenēs''), from ὁμός (''homos'', "same") and ἕτερος (''heteros'', "other, another, different") respectively, followed by γένος (''genos'', "kind"); -ous is an adjectival suffix. Alternate spellings omitting the last ''-e-'' (and the associated pronunciations) are common, but mistaken: ''homogenous'' is strictly a biological/pathological term whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expression Vector
An expression vector, otherwise known as an expression construct, is usually a plasmid or virus designed for gene expression in cells. The vector (molecular biology), vector is used to introduce a specific gene into a target cell, and can commandeer the cell's mechanism for protein synthesis to produce the protein Genetic code, encoded by the gene. Expression vectors are the basic tools in biotechnology for the protein production, production of proteins. The Vector (molecular biology), vector is engineered to contain regulatory sequences that act as Enhancer (genetics), enhancer and Promoter (biology), promoter regions and lead to efficient transcription of the gene carried on the expression vector. The goal of a well-designed expression vector is the efficient production of protein, and this may be achieved by the production of significant amount of stable messenger RNA, which can then be Translation (biology), translated into protein. The expression of a protein may be tightly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem Cell Biology
In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can change into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of cell in a cell lineage. They are found in both embryonic and adult organisms, but they have slightly different properties in each. They are usually distinguished from progenitor cells, which cannot divide indefinitely, and precursor or blast cells, which are usually committed to differentiating into one cell type. In mammals, roughly 50 to 150 cells make up the inner cell mass during the blastocyst stage of embryonic development, around days 5–14. These have stem-cell capability. ''In vivo'', they eventually differentiate into all of the body's cell types (making them pluripotent). This process starts with the differentiation into the three germ layers – the ectoderm, mesoderm and endoderm – at the gastrulation stage. However, when they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity in anatomical structures or genes between organisms of different taxa due to shared ancestry, ''regardless'' of current functional differences. Evolutionary biology explains homologous structures as retained heredity from a common descent, common ancestor after having been subjected to adaptation (biology), adaptive modifications for different purposes as the result of natural selection. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this from Aristotle's biology onwards, and it was explicitly analysed by Pierre Belon in 1555. A common example of homologous structures is the forelimbs of vertebrates, where the bat wing development, wings of bats and origin of avian flight, birds, the arms of primates, the front flipper (anatomy), flippers of whales, and the forelegs of quadrupedalis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (other)
Homology, homologous, homologation or homological may refer to: Sciences Biology *Homology (biology), any characteristic of biological organisms that is derived from a common ancestor *Sequence homology, biological homology between DNA, RNA, or protein sequences *Homologous chromosomes, chromosomes in a biological cell that pair up (synapse) during meiosis *Homologous recombination, genetic recombination in which nucleotide sequences are exchanged between molecules of DNA * Homologous desensitization, a receptor decreases its response to a signalling molecule when that agonist is in high concentration *Homology modeling, a method of protein structure prediction Chemistry *Homologous series, a series of organic compounds having different quantities of a repeated unit * Homologous temperature, the temperature of a material as a fraction of its absolute melting point *Homologation reaction, a chemical reaction which produces the next logical member of a homologous series O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autologous
Autotransplantation is the transplantation of organs, tissues, or even particular proteins from one part of the body to another in the same person ('' auto-'' meaning "self" in Greek). The autologous tissue (also called autogenous, autogeneic, or autogenic tissue) transplanted by such a procedure is called an autograft or autotransplant. It is contrasted with allotransplantation (from other individual of the same species), syngeneic transplantation (grafts transplanted between two genetically identical individuals of the same species) and xenotransplantation (from other species). A common example is the removal of a piece of bone (usually from the hip) and its being ground into a paste for the reconstruction of another portion of bone. Autotransplantation, although most common with blood, bone, hematopoietic stem cells, or skin, can be used for a wide variety of organs. One of the rare examples is autotransplantation of a kidney from one side of the body to the other. Ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protomer (structural Biology)
In structural biology, a protomer is the structural unit of an Protein quaternary structure, oligomeric protein. It is the smallest unit composed of at least one protein chain. The protomers associate to form a larger Protein quaternary structure, oligomer of two or more copies of this unit. Protomers usually arrange in cyclic symmetry to form closed point group symmetries. The term was introduced by Chetverin to make nomenclature in the Na+/K+-ATPase, Na/K-ATPase enzyme unambiguous. This enzyme is composed of two subunits: a large, catalytic α subunit, and a smaller glycoprotein β subunit (plus a proteolipid, called γ-subunit). At the time it was unclear how many of each work together. In addition, when people spoke of a dimer (chemistry), dimer, it was unclear whether they were referring to αβ or to (αβ)2. Chetverin suggested to call αβ a protomer and (αβ)2 a diprotomer. Thus, in the work by Chetverin the term protomer was only applied to a Protein quaternary structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Biology
Structural biology deals with structural analysis of living material (formed, composed of, and/or maintained and refined by living cells) at every level of organization. Early structural biologists throughout the 19th and early 20th centuries were primarily only able to study structures to the limit of the naked eye's visual acuity and through magnifying glasses and light microscopes. In the 20th century, a variety of experimental techniques were developed to examine the 3D structures of biological molecules. The most prominent techniques are X-ray crystallography, nuclear magnetic resonance, and Electron microscope, electron microscopy. Through the discovery of X-ray, X-rays and its applications to protein crystals, structural biology was revolutionized, as now scientists could obtain the three-dimensional structures of biological molecules in atomic detail. Likewise, Nuclear magnetic resonance spectroscopy, NMR spectroscopy allowed information about protein structure and dynamic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allogenic
In ecology, allogenic succession is succession driven by the abiotic components of an ecosystem. In contrast, autogenic succession is driven by the biotic components of the ecosystem. An allogenic succession can be initiated in a number of ways which can include: *Volcanic eruptions *Meteor or comet strike *Flooding *Drought *Earthquakes * Non-anthropogenic climate change Allogenic succession can happen on a time scale that is proportionate with the disturbance. For example, allogenic succession that is the result of non-anthropogenic climate change can happen over thousands of years. Allogenic succession can also vary widely in spatial scale. Some disturbances, like landslides or localized floods, affect only small patches of land and initiate short-term successional processes. Others, such as glaciation or long-term tectonic shifts, can transform entire regions over millennia. Human activities are also a major source of allogenic disturbance. Anthropogenic events, like defores ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autologous
Autotransplantation is the transplantation of organs, tissues, or even particular proteins from one part of the body to another in the same person ('' auto-'' meaning "self" in Greek). The autologous tissue (also called autogenous, autogeneic, or autogenic tissue) transplanted by such a procedure is called an autograft or autotransplant. It is contrasted with allotransplantation (from other individual of the same species), syngeneic transplantation (grafts transplanted between two genetically identical individuals of the same species) and xenotransplantation (from other species). A common example is the removal of a piece of bone (usually from the hip) and its being ground into a paste for the reconstruction of another portion of bone. Autotransplantation, although most common with blood, bone, hematopoietic stem cells, or skin, can be used for a wide variety of organs. One of the rare examples is autotransplantation of a kidney from one side of the body to the other. Ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medicine
Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, and Health promotion, promoting their health. Medicine encompasses a variety of health care practices evolved to maintain and restore health by the prevention (medical), prevention and treatment of illness. Contemporary medicine applies biomedical sciences, biomedical research, medical genetics, genetics, and medical technology to diagnosis (medical), diagnose, treat, and prevent injury and disease, typically through pharmaceuticals or surgery, but also through therapies as diverse as psychotherapy, splint (medicine), external splints and traction, medical devices, biologic medical product, biologics, and Radiation (medicine), ionizing radiation, amongst others. Medicine has been practiced since Prehistoric medicine, prehistoric times, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transduction (genetics)
Transduction is the process by which foreign DNA is introduced into a cell by a virus or viral vector. An example is the viral transfer of DNA from one bacterium to another and hence an example of horizontal gene transfer. Transduction does not require physical contact between the cell donating the DNA and the cell receiving the DNA (which occurs in conjugation), and it is DNase resistant ( transformation is susceptible to DNase). Transduction is a common tool used by molecular biologists to stably introduce a foreign gene into a host cell's genome (both bacterial and mammalian cells). Discovery (bacterial transduction) Transduction was discovered in ''Salmonella'' by Norton Zinder and Joshua Lederberg at the University of Wisconsin–Madison in 1952. In the lytic and lysogenic cycles Transduction happens through either the lytic cycle or the lysogenic cycle. When bacteriophages (viruses that infect bacteria) that are lytic infect bacterial cells, they harness the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
