translocation

Examples of translocation in the following topics:

• Transportation of Photosynthates in the Phloem

  • These sugars are transported through the plant via the phloem in a process called translocation.
  • The products from the source are usually translocated to the nearest sink through the phloem.
  • From there, they are translocated through the phloem where they are used or stored.
  • Phloem STEs have reduced cytoplasmic contents and are connected by sieve plates with pores that allow for pressure-driven bulk flow, or translocation, of phloem sap.
  • Once in the phloem, the photosynthates are translocated to the closest sink.

• Chromosomal Structural Rearrangements

  • Structural rearrangements of chromosomes include both inversions and translocations, which may have detrimental effects on an organism.
  • Cytologists have characterized numerous structural rearrangements in chromosomes, but chromosome inversions and translocations are the most common.
  • A translocation occurs when a segment of a chromosome dissociates and reattaches to a different, nonhomologous chromosome.
  • Notably, specific translocations have been associated with several cancers and with schizophrenia.
  • A reciprocal translocation occurs when a segment of DNA is transferred from one chromosome to another, nonhomologous chromosome.

• Group Translocation

  • Group translocation is a protein export or secretion pathway found in plants, bacteria, and archaea.
  • PEP group translocation, also known as the phosphotransferase system or PTS, is a distinct method used by bacteria for sugar uptake where the source of energy is from phosphoenolpyruvate (PEP).
  • The twin-arginine translocation pathway (Tat pathway) is a protein export or secretion pathway found in plants, bacteria, and archaea.
  • In contrast to the Sec pathway which transports proteins in an unfolded manner, the Tat pathway serves to actively translocate folded proteins across a lipid membrane bilayer.
  • Recall the following types of transport systems: PEP group translocation and the TAT pathway

• Naturally Occurring Antimicrobial Drugs: Antibiotics

  • In general, protein synthesis inhibitors work at different stages of prokaryotic mRNA translation into proteins, like initiation, elongation (including aminoacyl tRNA entry, proofreading, peptidyl transfer, and ribosomal translocation), and termination.
  • Macrolides (as well as inhibiting ribosomal translocation and other potential mechanisms) bind to the 50s ribosomal subunits, inhibiting peptidyl transfer.
  • Macrolides, clindamycin, and aminoglycosides (with all these three having other potential mechanisms of action as well) have evidence of inhibition of ribosomal translocation.
  • However, it does not engage in translocation and quickly dissociates from the ribosome, causing a premature termination of polypeptide synthesis.

• Suppression and Alteration of Microbiota by Antimicrobials

  • In addition, some microbial infections are due to translocation, the movement of advantageous bacteria to parts of the body where they might be harmful.
  • The treatment of translocated or pathogenic bacteria may necessitate the use of antibiotics that will kill symbiotic bacteria.

• Inhibiting Protein Synthesis

  • In general, protein synthesis inhibitors work at different stages of prokaryotic mRNA translation into proteins like initiation, elongation (including aminoacyl tRNA entry, proofreading, peptidyl transfer, and ribosomal translocation), and termination.
  • Macrolides, clindamycin, and aminoglycosides have evidence of inhibition of ribosomal translocation.

• Nitrification

  • Electron and proton cycling are very complex, but as a net result only one proton is translocated across the membrane per molecule of ammonium oxidized.
  • Nitrite reduction is much simpler, with nitrite being oxidized by the enzyme nitrite oxidoreductase coupled to proton translocation by a very short electron transport chain, again leading to very low growth rates for these organisms.

• Down Syndrome

  • A Robertsonian translocation in the karyotype of one of the parents may also cause Down syndrome.
  • A person with such a translocation is phenotypically normal.
  • Translocation Down syndrome is often referred to as familial Down syndrome.

• Embryonic Development of the Brain

  • These cells do so by somal translocation.
  • Radial fibers (also known as radial glia) can translocate to the cortical plate and differentiate either into astrocytes or neurons.
  • They do not resemble the cells migrating by locomotion or somal translocation.

• Metabolic Changes

  • These include: translocation of Glut-4 transporter to the plasma membrane and influx of glucose (3), glycogen synthesis (4), glycolysis (5) and fatty acid synthesis (6).