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Surfactant Protein C
Surfactant protein C (SP-C), is one of the Pulmonary surfactant#Proteins, pulmonary surfactant proteins. In humans this is encoded by the ''SFTPC'' gene. It is a membrane protein. Structure SFTPC is a 197-residue protein made up of two halves: a unique N-terminal propeptide domain and a C-terminal BRICHOS family, BRICHOS domain. The around 100-aa long propeptide domain actually contains not only the cleaved part, but also the mature peptide. It can be further broken down into a 23-aa helical transmembrane propeptide proper, the mature secreted SP-C (24-58), and a linker (59-89) that connects to the BRICHOS domain. The propeptide of pulmonary surfactant C has an N-terminal alpha-helical segment whose suggested function was stabilization of the protein structure, since the mature peptide can irreversibly transform from its native alpha-helical structure to beta-sheet aggregates and form amyloid fibrils. The correct intracellular trafficking of proSP-C has also been reported to d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonary Surfactant
Pulmonary surfactant is a surface-active complex of phospholipids and proteins formed by type II alveolar cells. The proteins and lipids that make up the surfactant have both hydrophilic and hydrophobic regions. By adsorbing to the air-water interface of alveoli, with hydrophilic head groups in the water and the hydrophobic tails facing towards the air, the main lipid component of surfactant, dipalmitoylphosphatidylcholine (DPPC), reduces surface tension. As a medication, pulmonary surfactant is on the WHO Model List of Essential Medicines, the most important medications needed in a basic health system. Function * To increase pulmonary compliance. * To prevent atelectasis (collapse of the alveoli or atriums) at the end of expiration. * To facilitate recruitment of collapsed airways. Alveoli can be compared to gas in water, as the alveoli are wet and surround a central air space. The surface tension acts at the air-water interface and tends to make the bubble smaller ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Protein
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane and can either penetrate the membrane (transmembrane) or associate with one or the other side of a membrane ( integral monotopic). Peripheral membrane proteins are transiently associated with the cell membrane. Membrane proteins are common, and medically important—about a third of all human proteins are membrane proteins, and these are targets for more than half of all drugs. Nonetheless, compared to other classes of proteins, determining membrane protein structures remains a challenge in large part due to the difficulty in establishing experimental conditions that can preserve the correct conformation of the protein in isolation from its native environment. Function Membrane proteins perform a variety of functions vital to the sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propeptide
A protein precursor, also called a pro-protein or pro-peptide, is an inactive protein (or peptide) that can be turned into an active form by post-translational modification, such as breaking off a piece of the molecule or adding on another molecule. The name of the precursor for a protein is often prefixed by ''pro-''. Examples include proinsulin and proopiomelanocortin, which are both prohormones. Protein precursors are often used by an organism when the subsequent protein is potentially harmful, but needs to be available on short notice and/or in large quantities. Enzyme precursors are called zymogens or proenzymes. Examples are enzymes of the digestive tract in humans. Some protein precursors are secreted from the cell. Many of these are synthesized with an N-terminal signal peptide that targets them for secretion. Like other proteins that contain a signal peptide, their name is prefixed by ''pre''. They are thus called pre-pro-proteins or pre-pro-peptides. The signal peptide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BRICHOS Family
The BRICHOS family consists of a variety of proteins linked to major diseases, each containing a 100 amino acid BRICHOS domain that is thought to have a chaperone function. These include BRI2, which is related to familial British and Danish dementia (FBD and FDD); Chondromodulin-I, related to chondrosarcoma; CA11, related to stomach cancer; and surfactant protein C Surfactant protein C (SP-C), is one of the Pulmonary surfactant#Proteins, pulmonary surfactant proteins. In humans this is encoded by the ''SFTPC'' gene. It is a membrane protein. Structure SFTPC is a 197-residue protein made up of two halves ... (SP-C), related to respiratory distress syndrome (RDS). Further reading * * * References {{DEFAULTSORT:Brichos Family Protein domains Protein families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amyloid
Amyloids are aggregates of proteins characterised by a fibrillar morphology of 7–13 nm in diameter, a beta sheet (β-sheet) secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the human body, amyloids have been linked to the development of various diseases. Pathogenic amyloids form when previously healthy proteins lose their normal structure and physiological functions ( misfolding) and form fibrous deposits in amyloid plaques around cells which can disrupt the healthy function of tissues and organs. Such amyloids have been associated with (but not necessarily as the cause of) more than 50 human diseases, known as amyloidosis, and may play a role in some neurodegenerative diseases. Some of these diseases are mainly sporadic and only a few cases are familial. Others are only familial. Some are iatrogenic as they result from medical treatment. Prions are an infectious form of amyloids that can act as a template to co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaperone (protein)
In molecular biology, molecular chaperones are proteins that assist the conformational folding or unfolding of large proteins or macromolecular protein complexes. There are a number of classes of molecular chaperones, all of which function to assist large proteins in proper protein folding during or after synthesis, and after partial denaturation. Chaperones are also involved in the translocation of proteins for proteolysis. The first molecular chaperones discovered were a type of assembly chaperones which assist in the assembly of nucleosomes from folded histones and DNA. One major function of molecular chaperones is to prevent the aggregation of misfolded proteins, thus many chaperone proteins are classified as heat shock proteins, as the tendency for protein aggregation is increased by heat stress. The majority of molecular chaperones do not convey any steric information for protein folding, and instead assist in protein folding by binding to and stabilizing folding intermed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surfactant Metabolism Dysfunction
Surfactant metabolism dysfunction is a condition where pulmonary surfactant is insufficient for adequate respiration. Surface tension at the liquid-air interphase in the alveoli makes the air sacs prone to collapsing post expiration. This is due to the fact that water molecules in the liquid-air surface of alveoli are more attracted to one another than they are to molecules in the air. For sphere-like structures like alveoli, water molecules line the inner walls of the air sacs and stick tightly together through hydrogen bonds. These intermolecular forces put great restraint on the inner walls of the air sac, tighten the surface all together, and unyielding to stretch for inhalation. Thus, without something to alleviate this surface tension, alveoli can collapse and cannot be filled up again. Surfactant is essential mixture that is released into the air-facing surface of inner walls of air sacs to lessen the strength of surface tension. This mixture inserts itself among water molec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstitial Lung Disease
Interstitial lung disease (ILD), or diffuse parenchymal lung disease (DPLD), is a group of respiratory diseases affecting the interstitium (the tissue and space around the alveoli (air sacs)) of the lungs. It concerns alveolar epithelium, pulmonary capillary endothelium, basement membrane, and perivascular and perilymphatic tissues. It may occur when an injury to the lungs triggers an abnormal healing response. Ordinarily, the body generates just the right amount of tissue to repair damage, but in interstitial lung disease, the repair process is disrupted, and the tissue around the air sacs (alveoli) becomes scarred and thickened. This makes it more difficult for oxygen to pass into the bloodstream. The disease presents itself with the following symptoms: shortness of breath, nonproductive coughing, fatigue, and weight loss, which tend to develop slowly, over several months. The average rate of survival for someone with this disease is between three and five years. The term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spidroin
Spidroins are the main proteins in spider silk. Different types of spider silk contain different spidroins, all of which are members of a single protein family. The most-researched type of spidroins are the major ampullate silk proteins (MaSp) used in the construction of dragline silk, the strongest type of spider silk. Dragline silk fiber is made up of two types of spidroins, spidroin-1 (MaSp1) and spidroin-2 (MaSp2). Spidroin is part of a large group of proteins called scleroproteins. This group includes other insoluble structural proteins such as collagen and keratin. A fiber of dragline spidroin is as thick and resistant as one of steel but is more flexible. It can be stretched to approximately 135% of its original length without breaking. Its properties make it an excellent candidate for use in various scientific fields. Structure Major ampullate spidroins are large proteins with an extension of 250-350kDa, with an average of 3500 amino acids. They represent a poly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
