In the above signalling diagram, hormone H binds to both an intracellular and a cell surface receptor. Initially you assume that hormone H must therefore be a small hydrophobic molecule. However, further analysis revealed that it is a large hydrophilic molecule. Knowing this, what would you need to add to this diagram to accurately reflect how these signalling events are possible and why? The csRu MRNA and protein are represented in the diagram below. mRNA 5' AUG 3' ribosome protein DNA ligand binding signal kinase transmembrane domain domain binding sequence domain domain

Histamine acts by binding to specialized membrane proteins called histamine H 1 receptors. These receptors, found in specific cells, are integral membrane proteins that possess seven transmembrane a-helical regions. The amino terminus of the protein is extracellular, while the C-terminus is cytoplasmic. The binding of histamine to the extracellular portion of the H 1 receptor prompts a conformational change in the intracellular C-terminus region of the protein. This conformational change triggers numerous intracellular signaling events that stimulate the immune response in cells containing the receptor. There are numerous anti-histamine drugs available commercially. Some of the most popular are shown here side by side with histamine: HCHS NH- Allegra H2N histamine Claritin Propose a reasonable mode of action by which these antihistamines exert their activity. Include relevant details about the system of your own choosing.

please identify amino acids in the N terminus in the picture below.

Look at the figure and predict what would happen if the SRPRNA was unable to stimulate the GTPase activities of the GTPbindingproteins within SRP and the SRP receptor.

While studying the secretory pathway, you make the following observation about proteins destined for the ER: Proteins translated in vitro in the absence of microsomes migrate more slowly on an SDS PAGE gel than those translated in the presence of microsomes.  What might account for the observed protein size difference?       A. SRP, present only in microsomes, and binds to and removes the signal sequence from the protein, resulting in a protein is smaller and migrates more quickly on a gel.       B.   Signal peptidase, present only in the microsomes, cleaves the signal sequence from the protein, making the protein smaller and therefore migrate more quickly.     C.   In vitro translated proteins tend to be larger due to a more stable poly A tail      D.   Signal peptidase, present only in the microsomes, adds a signal sequence to the protein, making the protein larger and therefore migrate more slowly.

The seed of the castor bean (Ricinus communis) contains large amounts of ricin, a deadly poison for animals, including humans. One of the two subunits of this toxin is a lectin that binds terminal N-acetylgalactosamine residues on glycoproteins on the surface of eukaryotic cells, allowing the other subunit to enter the cell and kill it by preventing proteins from being made. Select the possible antidotes that could prevent or reverse ricin-mediated entry of the toxin. a high concentration of N-acetylgalactosamine an oligosaccharide with the same structure as that recognized by ricin a compound that prevents synthesis of extracellular glycoproteins a compound that activates enzymes that break down glycogen into glucose an enzyme that degrades lipopolysaccharides

When you think about the primary structure of the mannose-6-P receptor, assuming that it is an integral membrane protein with one membrane-spanning domain and assuming that it has a ERSS, what are all of the different protein domains that must be present in this protein's primary structure to get it to where it needs to go and to carry out all of the functions/activities? (Draw a schematic of the protein structure/sequence and explain each region). What do you think would happen to a soluble protein that normally contains a KDEL tag (ER retrieval) if the tag was cleaved off (where would the protein end up)?

Please answer both, thank you

The enzymes GICNAC phosphotrasnferase is a key enzyme involved in the transporting of proteins from the trans-Golgi to the lysozyme. In addition to the catalytic function of the enzyme that involves certain sugars, what is the second critical function of this enzyme? O It recognizes internal signal sequences found on lysozyme-targeted proteins. O It drives the binding of a phosphorylated GlcNac group onto a mannose residue. O It facilitates the reversible binding of specific proteins to the M6P receptor O In is essential for the recruitment of clathrin triskelions to the budding vesicle.

The G-protein Ras is involved in proliferative signaling, and is mutated is a large fraction of human cancers. Almost all mutations in Ras mutate the glycine at codon 12. These mutations lock Ras in an active conformation. How will the GTPase activity of a Ras protein with a G12 mutation compare to a normal Ras protein without the mutation? (10 words maximum)