The Fourth Component: Enhancing The Patient-Doctor Relationship

2013 ◽  
pp. 142-164
Author(s):  
Moira Stewart ◽  
Judith Belle Brown ◽  
Thomas R Freeman
Keyword(s):  
Fourth Component

Component Deficiencies: 2. The Fourth Component

1987 ◽  
pp. 232-249
Author(s):  
Georges Hauptmann ◽  
Joëlle Goetz ◽  
Béatrice Uring-Lambert ◽  
Edouard Grosshans
Keyword(s):  
Fourth Component

scholarly journals Dating the primigenial C4-CYP21 duplication in primates.

Genetics ◽  
1993 ◽  
Vol 134 (1) ◽  
pp. 331-339 ◽  
Author(s):  
Y Horiuchi ◽  
H Kawaguchi ◽  
F Figueroa ◽  
C O'hUigin ◽  
J Klein
Keyword(s):  
World Monkey ◽  
Orthologous Genes ◽  
Pigtail Macaque ◽  
Single Chromosome ◽  
Old World ◽  
Histocompatibility Complex ◽  
Cyp21 Gene ◽  
Multiple Copies ◽  
Fourth Component ◽  
Flanking Regions

Abstract C4 and CYP21 are two adjacent, but functionally unrelated genes residing in the middle of the mammalian major histocompatibility complex (Mhc). The C4 gene codes for the fourth component of the complement cascade, whereas the CYP21 gene specifies an enzyme (cytochrome P450c21) of the glucocorticoid and mineralocorticoid pathways. The genes occur frequently in multiple copies on a single chromosome arranged in the order C4 ... CYP21 ... C4 ... CYP21. The unit of duplication (a module) is the C4-CYP21 gene pair. We sequenced the flanking regions of the C4-CYP21 modules and the intermodular regions of the chimpanzee, gorilla, and orangutan, as well as the intermodular region of an Old World monkey, the pigtail macaque. By aligning the sequences, we could identify the duplication breakpoints in these species. The breakpoint turned out to be at exactly the same position as that found previously in humans. The sequences flanking paralogous genes in the same species were found to be more similar to one another than sequences flanking orthologous genes in different species. We interpret these results as indicating that the original (primigenial) duplication occurred before the separation of apes from Old World monkeys more than 23 million years ago. The nature of the sequence at the breakpoint suggests that the duplication occurred by nonhomologous recombination. Since then, the C4-CYP21 haplotypes have been expanding and contracting by homologous crossing over which has homogenized the sequences in each species.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals ACTN4 Mediates SEPT14 Mutation-Induced Sperm Head Defects

Biomedicines ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 518
Author(s):  
Yu-Hua Lin ◽  
Chia-Yen Huang ◽  
Chih-Chun Ke ◽  
Ya-Yun Wang ◽  
Tsung-Hsuan Lai ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Model ◽  
Membrane Dynamics ◽  
Sperm Head ◽  
Cellular Processes ◽  
Germ Cell Line ◽  
Head Formation ◽  
Fourth Component ◽  
Related Proteins ◽  
Cellular Components

Septins (SEPTs) are highly conserved GTP-binding proteins and the fourth component of the cytoskeleton. Polymerized SEPTs participate in the modulation of various cellular processes, such as cytokinesis, cell polarity, and membrane dynamics, through their interactions with microtubules, actin, and other cellular components. The main objective of this study was to dissect the molecular pathological mechanism of SEPT14 mutation-induced sperm head defects. To identify SEPT14 interactors, co-immunoprecipitation (co-IP) and nano-liquid chromatography-mass spectrometry/mass spectrometry were applied. Immunostaining showed that SEPT14 was significantly localized to the manchette structure. The SEPT14 interactors were identified and classified as (1) SEPT-, (2) microtubule-, (3) actin-, and (4) sperm structure-related proteins. One interactor, ACTN4, an actin-holding protein, was selected for further study. Co-IP experiments showed that SEPT14 interacts with ACTN4 in a male germ cell line. SEPT14 also co-localized with ACTN4 in the perinuclear and manchette regions of the sperm head in early elongating spermatids. In the cell model, mutated SEPT14 disturbed the localization pattern of ACTN4. In a clinical aspect, sperm with mutant SEPT14, SEPT14A123T (p.Ala123Thr), and SEPT14I333T (p.Ile333Thr), have mislocalized and fragmented ACTN4 signals. Sperm head defects in donors with SEPT14 mutations are caused by disruption of the functions of ACTN4 and actin during sperm head formation.

EFFECTS OF LIPID MATERIALS ON GUINEA PIG COMPLEMENT

1961 ◽  
Vol 39 (4) ◽  
pp. 757-762 ◽  
Author(s):  
R. K. Guthrie ◽  
J. R. Dowdy ◽  
D. C. Hinkle
Keyword(s):  
Linoleic Acid ◽  
Guinea Pig ◽  
Stearic Acid ◽  
Prior Work ◽  
Fourth Component ◽  
Measurable Change

Prior work has shown that the fourth component of guinea pig complement is increased following antigen injection. This report concerns the changes in C′4 following injection of non-antigenic materials. Injection of cholesterol, ergosterol, or linoleic acid does not cause any measurable change in C′ or C′4. Injection of oleic or of stearic acid causes a significant increase in C′4 but has no effect on C′

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