Ap2 Lab Report

Apoliproteins are important players in cholesterol homeostasis. ApoA-I acting as a major HDL component is involved in both HDL biosynthesis and transport. In diseases of the CNS where BBB is compromised, such as MS a healthy cholesterol homeostasis becomes extremely important for neuronal status and regeneration. In as much as S1P receptor agonist fingolimod, Apo-I’s function is not completely understood in this disorder. However all implications are in favor of positive neuroprotective effect of this lipoprotein on the CNS.

Lysosomes are known as the “Digestive organelle” of the cell, with their main function being to digest intracellular components. They’re characterized by a low pH and many different acidic hydrolysis, giving them an optimum acidic environment for breaking down larger macromolecules such as oligosaccharides and complex lipids. Once broken down, their building blocks are then exported to the cytosol where they can be reused as nutrients in cellular metabolism. Impairment of lysosomes to execute this process has many effects that could cause disease as well as death.

In the lysosome, food from the cell is digested. This food is digested by strong enzymes. The highly acidic pH of the lumen in the lysosome makes an appropriate home to these digestive enzymes, which break down proteins, nucleic acids and lipids (Schechter, Lecture #8). The lysosome is most likely to have the most built and large lipids, after they have been exchanged through different organelles in the cell. (Nature, 55) The lysosome could become clogged with very large and complex lipids because if these enzymes stop doing their jobs, or stop working as well, molecules could easily pile up within the

How does dysbindin-1 regulate Drp1 oligomerization? Dysbindin-1 has been detected on mitochondrial outer membranes by electron microscopy 28. It is possible that dysbindin-1 binds to Drp1 to enhance its oligomerization. To test this possibility, we transfected HEK-293 cells with YFP-Drp1 along with HA-tagged dysbindin-1C or -1A, and used an anti-HA antibody to immunoprecipitate dysbindin-1 at 2 days after transfection. Drp1 was detected in the immunoprecipitation product from cells transfected with dysbindin-1C, but not with -1A plasmid (Figure 4G), indicating that

Hsp90 is a cytoplasmic protein which is globular in structure, being predominantly polar outside and nonpolar inside. Hsp90 can be activated through the binding with ATP where it has a specific ATP-binding site. It contains two conformational states, an open ATP-bound state and a closed ADP-bound state. There are three functional domains in Hsp90. There is the N-terminus binding domain where ATP-binding occurs, the

I hypothesize that O-GlcNAcylation of specific sites on Sec24C/D regulate COPII vesicle trafficking and mediate protein-protein interactions. The experiments proposed below will test this hypothesis by completion of my three aims: 1) Determine how O-GlcNAcylation of Sec24C/D affects COPII vesicle secretion under normal and ER stress conditions, 2) Characterize Sec24C/D O-GlcNAc mediated protein-protein interactions and their role in vesicle trafficking and, 3) Examine the Interplay between O-GlcNAcylation and phosphorylation on Sec24C/D in cell cycle progression and vesicle trafficking.

The GM2 activator protein also assists in the transport of the GM2 ganglioside to the lysosome, allowing for further degradation by β-hexosaminidase A. Lysosomes are organelles found in eukaryotic cells that contain important enzymes, such as β-hexosaminidase A, that help to breakdown various substances. Upon reaching the lysosome, the β-subunit of β-hexosaminidase A binds to the GM2 activator protein. The β-subunit of β-hexosaminidase A further activates the α-subunit of β-hexosaminidase A. As a final step in degradation, the α-subunit of β-hexosaminidase A cleaves the terminal N-acetylgalactosamine group from the GM2 ganglioside. This cleavage allows for the GM2 ganglioside to be fully digested by the

50S ribosomal subunits binds to the 30s ribosomal unit, giving rise to a complete 70s ribosome. Initial factors(IF-1, IF-2, IF-3) are required for the formation of the initiation complex described above.

SGLT1, involved in the active transport, activated on the side of intestinal lumen. These transport protein requires ATP to bind Na+ on one side and glucose/galactose on the other side. Na+ATPase pump both sodium and glucose molecules through and then out of the cell membrane and they are lastly transported to the bloodstream by the assistance of GLUT2. After meals, blood glucose level raises up in the intestinal lumen. Glucose needs to be transported into the enterocyte through facilitated transport with help of GLUT2. GLUT2 is activated

Prior to the treatment of the ribosome, the P sites would function as the binding force holding the growing polypeptide chain of the amino acid to the peptidyl site. This is in correlation to the process of translation, in which the RNA is translated into a polypeptide chain with the aid of Ribosomal RNA and transfer RNA. To begin the process prior to treatment, first the initiation process starts through tRNA and methionine serving as catalyst to form a complete ribosome in an empty A-site. The RNA’s from the A site are linked to the P site which allows the appropriate amino acids to connect with RNA using the A site as an amino acid storage for the polypeptide chain. Without the P site, or the blockage of it, there would be no

Cell membranes of eukaryotes are complex in structure, comprised of a highly regulated heterologous distribution of lipids and proteins (Hanada, 2010). This distribution is determined to some extent by the location and topology of lipid synthases, and results from the trafficking of proteins and lipids (Hanada, 2010). Within the cell, transport vesicles and tubules mediate trafficking by loading desired sets of proteins at one organelle and delivering them to the next (Hanada, 2010; Kumagai et al., 2005). Lipid influx routes such as the endocytosis of membrane lipids add further to the diversity (Hanada, 2010). The result is an asymmetric distribution of protein and lipid types across the membrane phospholipid bilayer (Hanada, 2010).

al, 2015). I truly realized the importance of post-translational modification and its role in cellular function and potential role for human disease. The article “Identification of lysine succinylation as a new post-translational modification” by Zhihong Zhang et. al seeks to illustrate the presence and verification of lysine succinylation through the process of MS/MS tandem mass spectroscopy, HPLC high performance chromatography, isotopic succinate labeling and western blot to demonstration that post-translational modification lysine succinylation could have important cellular significance (Zhang et. al, 2015). The lysine is very important because it undergoes a variety of modification and is important in protein structure and function (Zhang et. al, 2011). The role of post-translation modification is very important because any disturbance could have large impact since any change can drastically alter the structure of a protein and thus change the function its function (Doreing et. al, 2015).

Lysosome plays important role in cells’ behavior, it not only the degradation and recycle place for cells, but it also associated with cellular processes such as autophagy and signaling. Especially in cancer cells, the lysosomes are greater in number, larger, more active than normal cells. [1] The mechanism for lysosome in cancer cells is that lysosome can release certain cathepsins, which is a kind of virtual acidic hydrolases from tumor cells into the extracellular space, which lead to cancer cells’ progression and death by apoptosis and apoptosis-like pathways. [2] On the one hand, the cathepsins contribute to the degradation of intracellular substrates, regulation and recycle of extracellular substrates. On the other hand, the cathepsins control degradation of secretory proteins by crinophagy and degradation

Among the three promising PI(3)P-interacting partners, the mammalian orthologues of PfHsp70-1 have been reported to bind several anionic phospholipids including phosphoinositides, implicating conserved lipid-binding pockets in PfHsp70-1. Furthermore, the human Hsp70 has been shown to be associated with lysosomes via binding to a lysosomal membrane lipid and may stabilize the lysosomal membrane under cellular stresses. The functional counterpart of lysosome in Plasmodium is the acidic food vacuole where hemoglobin is digested. The fact that PI(3)P is heavily

SDS-PAGE and Western blot 39 4. Results 41 4.1. How does UPF1 bind its substrates? 41 4.1.1. Introduction 41 4.1.2.