102. Yeast and mammals share very similar cell communication molecules and pathways. What does this suggest about yeast and mammals?

1. You are interested in the eukaryotic protein/enzyme Thiolase, which is 200 amino acids in length. Because Thiolase is only active in the peroxisome (an organelle) you know there must be a peroxisomal localization signal sequence in the protein. Sub-cellular Location Construct of GFP protein In order to be able to visualize the Thiolase protein in a cell, you create a fusion Cytosol construct with the gene for Thiolase and the GFP gene for Green Fluorescent Protein (GFP). 200 Thiolase Peroxisome GFP You also make a series of deletions in the 50 200 Peroxisome gene for Thiolase, all fused with the GFP GFP 100 200 gene. Numbers on top of the constructs GFP Peroxisome represent amino acid positions. 125 200 Cytosol GFP You express each construct in a mammalian 150 200 cell and use a microscope to visualize where the Thiolase-GFP protein gets trafficked. cytosol GEP 150 Peroxisome GFP Using the data provided, where must the peroxisomal localization signal sequence be in the Thiolase…

2. You perform a series of experiments on the synthesis of the pituitary hormone prolactin, which is a single polypeptide chain 199 amino acids long. In the first experiment, the MRNA coding for prolactin is translated in a cell-free protein synthesizing system containing ribosomes, amino acids, tRNAs, aminoacyl-TRNA synthetases, ATP, GTP, and the appropriate initiation, elongation, and termination factors. Under these conditions, a polypeptide chain 227 amino acids long is synthesized. In a second experiment, the MRNA is translated in the same cel1-free system to which you have added SRP. In this case, translation stops after a peptide about 70 amino acids long has been produced. In a third experiment, you use the same cell-free translation system to which you have added both SRP and endoplasmic reticulum vesicles, and you find that that the prolactin MRNA now produces a polypeptide that is 199 amino acids long. A) Explain these results.

Can you help me with this question?

Professor Greg Hermann and his lab investigate the biogenesis of gut granules in C. elegans. Gut granules are a type of lysosome-related organelle (LRO) uniquely found in the intestinal system of C. elegans from early embryonic development to adulthood. Whereas lysosomes facilitate digestion of materials, LROs are more diverse in their functions, due to the different factors (proteins, chemicals, etc.) contained in the LRO. To achieve the unique compositions of molecules in LROs, identify which kind of transmembrane transport must be employed at some point in LRO biogenesis: passive transport (facilitated diffusion) or active transport. Briefly defend your choice

6.  explain what coupled transcription-translation is, and why it occurs in prokaryotes but not eukaryotes

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1. Describe the process by which an integral membrane glycoprotein goes from mRNA to being an integral membrane protein 2. Describe in detail the initiation of translation in eukaryotes versus prokaryotes. All steps. 3. Compare and contrast gated transport and transmembrane transport of mitochondria. Specific details are required. 4. Compare and contrast regulation of gene expression between prokaryotes and eukaryotes 5. The plasma membrane, as an example, is described as a fluid mosaic. Why? (hint: LOTS of details)

5. In what organelle of the cell are amino acids synthesized from mRNA?