They form between 25–50% of the protein-coding genes of the multicellular organisms. The chicken lysozyme gene is an example of a solitary protein-coding gene with four exons and three introns. A genes family, on the other hand, is a group of genes bearing similar features as DNA’s building blocks (nucleotides) (Galluzzi 126). They contain instructions for making new products such as proteins. In some cases, genes are grouped together to form a family on the basis of product-protein interactions to achieve a certain
Centrioles are non-membranous organelles that are usually located near the Golgi apparatus and the nucleus . Most cells have two centrioles, each made up of nine sets of three microtubules (described later on page #39). Centrioles are hollow and cylindrical and lay next to each other at 90 degree angles . Vital to cellular division, the centrioles function to separate homologous chromosomes in meiosis 1 and sister chromatids during mitosis and meiosis 2. During these processes, the centrioles form fibers, called spindle and aster fibers, which attach to the centromeres and line up the chromosomes or homologous pairs of chromosomes on the metaphase plate.
Both of the subunits of HIF-1 complex belong to the same family of proteins that contain basic helix-loop-helix (HLH) and PER-ARNT-SIM (PAS) motifs. These two motifs are important for the formation of heterodimerisation between the HIF-α and HIF-β subunits (Manolescu et al., 2009). Previous historyin HIF system tells that there are three HIF-α subunits are reported i.e. HIF-1α, HIF-2α or HIF-3α (Hogenesch et al., 1997). Out of the three α-subunits, HIF-1α and HIF-2α are the best studied.
Pradar Willi and Angleman Syndrome Website Lecture Group 3 Background The Chromosome Chromosomes are located in the nucleus of cells. They are what make up the genetic information that allows all organisms to be unique. Chromosomes consist of Deoxyribonucleic acid that are bundled up tightly to form the larger chromosome structure. In human cells there are usually 46 chromosomes. 23 inherited from the father called paternal and 23 from the mother called maternal.
There are three kinds of DNA with specific functions. First, messenger RNA (mRNA) is responsible for transcribing the information from the DNA. That information is then sent to the ribosomes and cytoplasm. The second, transfer RNA (tRNA) transfers amino acids to the mRNA in a ribosome. The third, ribosomal RNA (rRNA), translates the information from the mRNA and the tRNA.
ER is divided into two types: rough ER, having ribosomes attached to its outersurface, and smooth ER, lacking ribosomes. The two types of ER have different functions in the cell, with rough ER to be mainly involved in protein modification and smooth ER being more of a jack-of-all-trades (many functions). Both types of ER can manufacture new lipids for export to other cellular membranes. (Johnson et al, 2010) The Rough ER is a site of protein
Thus, CerS determine the acyl chain length of sphingolipids, including ceramides, sphingomyelin and glycosphingolipids. The six CerS are differently expressed among tissues and cell types, yielding to distinct sphingolipids-acyl chain length profiles for each cell/tissue. As an example, in the brain, CerS1 (which targets C18 acyl-chains) is distributed primarily in neurons, whereas CerS2, responsible for the synthesis of C22-C24 acyl-chain sphingolipids, is expressed specifically in oligodendrocytes and Schwann cells.38 The next step in de novo synthesis is the desaturation of dihydro-ceramides to generate ceramides, by the dihydroceramide desaturase (DES). Ceramides can be further metabolized to sphingomyelin, by the addition of a phosphocholine head group from phosphatidyl-choline by the sphingomyelin synthases, or to glycosphingolipids, by the addition of a sugar group. Serine-palmitoyl transferase can alternatively utilize alanine instead of serine resulting in the synthesis of deoxyceramides, which
Summary Endoplasmic reticulum is a eukaryotic organelle that forms interconnected network of cisternae, vesicles and tubules within the cells[1,2]. There are two types of endoplasmic reticulum: rough and smooth endoplasmic reticulum. The rough endoplasmic reticulum is covered with ribosomes in its membrane, these ribosomes are the site of protein synthesis. The ribosome free endoplasmic reticulum also know as smooth endoplasmic reticulum, its functions including lipid synthesis, drug detoxification and regulation of calcium concentration[2,3,4]. Furthermore, the endoplasmic reticulum can be isolated from animal soft by centrifugation method and the production form isolation can be used to study the metabolism of lipid and the recovery
In Mitosis the two daughter cells are identical from a single parent cell. Mitosis produces the most cells in the body. In Meiosis the daughter cells are not identical and splits the chromosomes in half which produces gametes. This makes the cells identity unique. 2.
Heterozygous missense mutations in HTRA2/OMI has been found in the “random” cases of Parkinson’s disease. HtrA2 is homologous with bacterial Deg proteases, localizes to the mitochondrial intermembrane space where it protects against mitochondrial