* More than 40 proteins and glycoproteins involved in the complement system are synthesized by the liver, macrophages, epithelial cells, they are present in the blood in plasmatic form, membrane, some have an enzymatic activity, regulator or membrane receptorThese are elements of the humoral innate immune response, they fight infections, purify immune complexes and apoptotic bodies.
<span>There are indeed three ways to activate the complement:</span>
Classical pathway: Activated by Immunoglobulins in immune complexes, aggregated Immunoglobulins, DNA, CRP, apoptotic bodies .......it involves nine fractions, starting with C1, then C4, C2, C3, to form a classical C5 convertase, then, activation of C5, C6, C7, C8, C9.
Alternative pathway: activated by polysaccharides (bacterial endotoxin), vascular wall poor in sialic acid, aggregated IgE ...C3b like is the first component in the alternate channel cascade, it will create an amplification loop, and form an alternative C5 convertase.
Lecithin pathway: Activated by mannose, fucose (carbohydrate of microorganisms)The first component is the complex MBL / MASP1 / MASP2: "mannose-binding protein": works according to the same principle as the complex C1 of the classical way (MASP2 cleaves the C4 and the rest of the cascade is equivalent to that of the classical way).
the three ways have the same outcome: A C5 convertase (formed by one of the pathways) cleaves C5 into C5a and C5b: C5b is deposited far from other fractions on the antigenic surface. The fixation of C5b in the cell is followed by that of C6, C7, C8, and C9 (9 molecules of C9): formation of the membrane attack complex (MAC) ==> Death of the cell by osmotic shock
Answer:
Indivisuals with producing an abnormal form of extracellular protein fibrillin are suffering from Marfan syndrome ehich is caused by genetic mutation in the FBN1 gene.
Explanation:
Gene mutations in FBN1 gene results in the production of an abnormal extracellular matrix fibrillin-1 protein that cannot function properly. These gene mutations basically reduce the amount of fibrillin-1 produced by the cell, alter the structure of fibrillin-1, or causes the impairment of the transport of fibrillin-1 out of the cell.
As a result, protein is poorly incorporated into extracellular matrix. Hence, indivisuals with Marfan syndrome present following symptoms
Tall stature.
Disproportionately long arms, legs and fingers.
Sternum either protrudes outward or dips inward.
Arched palate and crowded teeth.
Heart murmurs.
Extreme nearsightedness.
There are several mutations that benefit the organism.A well known example is the antibiotic resistance developed by bacteria, which aid in their survival even when they are exposed to a given antibiotic. A single gene mutation in wild almond trees resulted in a variety that no longer synthesizes amygdalin.
Glycolysis, Krebs cycle, electron transport chain
