A Functional Unit with Small Variety of Highly Reliable Cells

2008 ◽  
Author(s):  
Kazunori Suzuki ◽  
Takashi Nakada ◽  
Masaki Nakanishi ◽  
Shigeru Yamashita ◽  
Yasuhiko Nakashima
Keyword(s):  
Functional Unit ◽  
Small Variety

scholarly journals B0AT1 amino acid transporter complexed with SARS-CoV-2 receptor ACE2 forms a heterodimer functional unit: in situ conformation using radiation inactivation analysis

Function ◽  
2021 ◽  
Author(s):  
Bruce R Stevens ◽  
J Clive Ellory ◽  
Robert L Preston
Keyword(s):  
Amino Acid ◽  
Membrane Trafficking ◽  
Functional Unit ◽  
Membrane Vesicles ◽  
High Energy ◽  
Amino Acid Transporter ◽  
Neutral Amino Acid ◽  
Transport Activity ◽  
Acid Transporter

Abstract The SARS-CoV-2 receptor, Angiotensin Converting Enzyme-2 (ACE2), is expressed at levels of greatest magnitude in the small intestine as compared to all other human tissues. Enterocyte ACE2 is co-expressed as the apical membrane trafficking partner obligatory for expression and activity of the B0AT1 sodium-dependent neutral amino acid transporter. These components are assembled as an [ACE2: B0AT1]2 dimer-of-heterodimers quaternary complex that putatively steers SARS-CoV-2 tropism in the gastrointestinal (GI) tract. GI clinical symptomology is reported in about half of COVID-19 patients, and can be accompanied by gut shedding of virion particles. We hypothesized that within this 4-mer structural complex, each [ACE2: B0AT1] heterodimer pair constitutes a physiological “functional unit.” This was confirmed experimentally by employing purified lyophilized enterocyte brush border membrane vesicles that were exposed to increasing doses of high-energy electron radiation from a 16 MeV linear accelerator. Based on established target theory, the results indicated the presence of Na+-dependent neutral amino acid influx transport activity functional unit with target size mw = 183.7 ± 16.8 kDa in situ in intact apical membranes. Each thermodynamically stabilized [ACE2: B0AT1] heterodimer functional unit manifests the transport activity within the whole ∼345 kDa [ACE2: B0AT1]2 dimer-of-heterodimers quaternary structural complex. The results are consistent with our prior molecular docking modeling and gut-lung axis approaches to understanding COVID-19. These findings advance the understanding of the physiology of B0AT1 interaction with ACE2 in the gut, and thereby potentially contribute to translational developments designed to treat or mitigate COVID-19 variant outbreaks and/or GI symptom persistence in long-haul Post-Acute Sequelae of SARS-CoV-2 (PASC).

scholarly journals Three Subfamilies of Pheromone and Receptor Genes Generate Multiple B Mating Specificities in the Mushroom Coprinus cinereus

Genetics ◽  
2000 ◽  
Vol 154 (3) ◽  
pp. 1115-1123 ◽  
Author(s):  
John R Halsall ◽  
Michael J Milner ◽  
Lorna A Casselton
Keyword(s):  
Southern Blotting ◽  
Transmembrane Domain ◽  
Functional Unit ◽  
Large Family ◽  
Coprinus Cinereus ◽  
Multidrug Transporter ◽  
Type Locus ◽  
Allele Specific ◽  
Unique Specificity ◽  
Major Facilitator

Abstract The B mating type locus of the basidiomycete Coprinus cinereus encodes a large family of lipopeptide pheromones and their seven transmembrane domain receptors. Here we show that the B42 locus, like the previously described B6 locus, derives its unique specificity from nine multiallelic genes that are organized into three subgroups each comprising a receptor and two pheromone genes. We show that the three genes within each group are kept together as a functional unit by being embedded in an allele-specific DNA sequence. Using a combination of sequence analysis, Southern blotting, and DNA-mediated transformation with cloned genes, we demonstrate that different B loci may share alleles of one or two groups of genes. This is consistent with the prediction that the three subgroups of genes are functionally redundant and that it is the different combinations of their alleles that generate the multiple B mating specificities found in nature. The B42 locus was found to contain an additional gene, mfs1, that encodes a putative multidrug transporter belonging to the major facilitator family. In strains with other B mating specificities, this gene, whose functional significance was not established, lies in a region of shared homology flanking the B locus.

scholarly journals π-Conjugated Trigonal Planar [C(NH2)3]+ Cationic Group: A Superior Functional Unit for Ultraviolet Nonlinear Optical Materials

ACS Omega ◽  
2021 ◽  
Author(s):  
Yunxia Song ◽  
Min Luo ◽  
Donghong Lin ◽  
Chensheng Lin ◽  
Zujian Wang ◽  
...  
Keyword(s):  
Optical Materials ◽  
Nonlinear Optical ◽  
Functional Unit ◽  
Nonlinear Optical Materials ◽  
Cationic Group ◽  
Group A

scholarly journals The functional unit of sarcoplasmic reticulum Ca2+-ATPase. Active site titration and fluorescence measurements.

1982 ◽  
Vol 257 (14) ◽  
pp. 8300-8307 ◽  
Author(s):  
J P Andersen ◽  
J V Møller ◽  
P L Jørgensen
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Active Site ◽  
Functional Unit ◽  
Fluorescence Measurements

scholarly journals Cribellate thread production as model for spider’s spinneret kinematics

2021 ◽  
Author(s):  
Margret Weissbach ◽  
Marius Neugebauer ◽  
Anna-Christin Joel
Keyword(s):  
Molecular Structure ◽  
Mechanical Properties ◽  
Fibre Type ◽  
Material Science ◽  
Spider Silk ◽  
Functional Unit ◽  
Material Strength ◽  
Spinning Process ◽  
Fibre Spinning ◽  
House Spider

AbstractSpider silk attracts researchers from the most diverse fields, such as material science or medicine. However, still little is known about silk aside from its molecular structure and material strength. Spiders produce many different silks and even join several silk types to one functional unit. In cribellate spiders, a complex multi-fibre system with up to six different silks affects the adherence to the prey. The assembly of these cribellate capture threads influences the mechanical properties as each fibre type absorbs forces specifically. For the interplay of fibres, spinnerets have to move spatially and come into contact with each other at specific points in time. However, spinneret kinematics are not well described though highly sophisticated movements are performed which are in no way inferior to the movements of other flexible appendages. We describe here the kinematics for the spinnerets involved in the cribellate spinning process of the grey house spider, Badumna longinqua, as an example of spinneret kinematics in general. With this information, we set a basis for understanding spinneret kinematics in other spinning processes of spiders and additionally provide inspiration for biomimetic multiple fibre spinning.

scholarly journals TEMPERATURE CHARACTERISTICS FOR PULSATION FREQUENCY IN GONIONEMUS

1928 ◽  
Vol 11 (5) ◽  
pp. 547-562 ◽  
Author(s):  
Ernst Wolf
Keyword(s):  
Critical Temperature ◽  
Functional Unit ◽  
Temperature Characteristic ◽  
Nerve Ring ◽  
Pulsation Frequency ◽  
Sense Organs ◽  
Critical Temperatures ◽  
Temperature Characteristics ◽  
System A ◽  
Definite Temperature

The frequency of contraction of the bell of Gonionemus was studied in relation to temperature, with intact animals and also where different operations were made on the nervous system. A number of values of µ are found for intact animals namely 8,100±, 10,500±, 32,000± and 22,500±, with critical temperatures at 9.6°, 12.3°, and 14.0°. Four different classes of operations were used: (1) Animals where the nerve ring was cut on two opposite sides of the bell; the µ values found are 10,500± and 21,300±, with a critical temperature at 13.4°. (2) Animals with four cuts through the nerve ring gave µ = 10,600 ± and µ = 21,000, with a critical temperature at 13.1°. (3) In animals where the bell was cut in half the temperature characteristic was found to be 16,900. And finally (4) in the animals where the nerve ring was totally removed µ values of 8,100, 16,000±, and 29,000 were found, with critical temperatures at 15.0° and 9.4°. These results are discussed from the standpoint of the theory which supposes that definite "temperature characteristics" may be associated with the functional activity of particular elements in a complex functional unit, and that these elements may be separately studied and identified by suitable experimental procedures involving the magnitudes of the respective temperature characteristics and the locations of associated critical temperatures. The swimming bell of medusæ with its marginal sense organs permits a fairly direct approach to such questions. It is found that even slight injuries to the marginal nerve ring, for example, produce specific modifications in the temperature relations which are different from those appearing when the organism is cut in half.

Synthesizing distributed pipelining systems with timing constraints via optimal functional unit assignment and communication selection

2018 ◽  
Vol 26 ◽  
pp. 332-343 ◽  
Author(s):  
Weiwen Jiang ◽  
Edwin H.-M. Sha ◽  
Xianzhang Chen ◽  
Lin Wu ◽  
Qingfeng Zhuge
Keyword(s):  
Functional Unit ◽  
Timing Constraints

Comparative Life Cycle Assessment of Autoclaved Concrete Blocks and Fired Blocks in China

2018 ◽  
Vol 913 ◽  
pp. 1018-1026
Author(s):  
Yan Qiong Sun ◽  
Yu Liu ◽  
Su Ping Cui
Keyword(s):  
Sensitivity Analysis ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Data Quality ◽  
Human Health ◽  
Functional Unit ◽  
Cement Production ◽  
Terrestrial Ecotoxicity ◽  
Concrete Blocks

In this paper, a variety of blocks were grouped into the autoclaved blocks and fired blocks as far as the productive technology is concerned. In order to compare the life cycle impacts of the two kinds of the blocks, a life cycle assessment of two products on the functional unit 1m3 was carried out through the exploitation of mineral stage, transportation stage and the production of the blocks stage on the considering of the resource and energy consumption and the pollutant discharges. The results demonstrated that the fired blocks appeared to have less impact than autoclaved concrete blocks on human health, marine ecotoxicity toxicity and terrestrial ecotoxicity toxicity nearly 30%. The raw coal led to the serious impacts on the fossil depletion through the cement production stage of the autoclaved concrete blocks accounting for 45.86% and the gangue exploitation stage of the fired blocks accounting for 42.5%. Assessment of the data quality that the data was of pretty high or within the permission. The sensitivity analysis and contribution analysis assessment showed that the conclusion were robust.

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