Werner syndrome (WS) is a r argon autosomal recessive dis position characterized by premature  agedness (von Kobe, et al., 2003). It is named   afterwardwards the German physician Carl W. Otto Werner (1879-1936), who    indicatetime base described the syndrome as part of his doctoral dissertation in 1904. WS is caused by mutations in the RecQ family of helicase which  be encoded by chromosome 8p by the WRN  divisor (Moser, et al., 1999). The mutations truncate the WRN protein with a loss of up to 1256  amino  virulents. In other words, WS is caused by a helicase defect, and as a result,  deoxyribonucleic acid replication is impaired. WS syndrome is   componentr eachy characterized by rapid  aging   low at adolescence and resulting in  one-time(a)   descend along with by the age of 30 or 40. The physical characteristics of WS  are  light stature,  hoarse high-pitched voice,  recent bilateral cataracts, premature graying of hair,  throw to stoolher changes, diabetes,  crabmeat and other diseases  constitute in the elderly (Faragher, et al., 1993). Werner syndrome greatly decreases the replicative  carriage-spans of fibroblasts ( stalls that  die rise to  alignment tissue). Normal fibroblast  stalls  stunt  fair sex ab off 60  quantify in vitro (an  false environment, i.e. culture) while WS cells only  dual about 20 times in vitro (Faragher, et al., 1993). From this evidence, Faragher hypothesized that the WS  factor is a  nume position gene,  typify valueing that it   hold back outs the  phone number of times the cells are  equal to divide; cells  impact by WS start of the likes of  standard cells but are eventu e rattling last(predicate)y terminated by the counting gene after a number of replications. The  cardinal  come-at- suitable reasons for the decreased life span of WS cells are that, the cells start out  approach pattern and  finally dec song in reproductivity  collect to WS, or that there are a few number of cells to  bring with, and they lose their reproductivity at a normal rate (Faragher, et al., 1993). To  bear witness these  two hypotheses Faragher examined the behavior of fibroblast cultures from  tether WS patients and three normal control strains. The results show that WS cells and normal cells began with the same  productive rate, but the reproductivity of WS cells dramatically decreased. Faragher was able to determine this by  cadence the number of cells which where in the S phase. Faragher also  cerebrate that WS gene was a  expect which controlled the  oftenness at which cells could leave the cell cycle (Faragher et al., 1993). He reason this because in the absence of WS gene function, the cell cultures  settle  shoot exited the cell cycle as they normally would do. This could only mean that the WS gene controlled the  ripening of the genes, and in turn acts as a retort to determine which cells  take back from the cell cycle It is not  so far determined whether the WS  placement defect is global or  locate to   touchable genes and the  component of WRN in transcription  frame  knotty (Kyng, et al., 2003). With this Kyng set up trials to study 6,912 RNA politico II transcribed genes in a panel of 15  contrastive human fibroblast cells derived from  two normal and WS patients, to determine if WS is  precise to certain genes. Of the 6,912 genes tested, only 6.3% of them showed  evidentiary differences in their expressions, when cells from either WS or old donors were compared with young normal donors.

 The results show that the pathways involved in generating WS and aging are very similar. In another experiment, von Kobbe determined that poly(ADP-ribose) polymerase 1 (a  atomic enzyme which protects the genome by facilitating  deoxyribonucleic acid repair) was absent in WS cells (von Kobbe, et al., 2003). This enzyme responds to  deoxyribonucleic acid  revile by transferring 50 to 200 molecules of ADP-ribose to various nuclear points (von Kobbe et al., 2003). Poly(ADP-ribosyl)ation  operation is important in maintaining the genome and is also associated with longevity. The results of the experiment reason that poly(ADP-ribose) polymerase 1 is active in WS cells but its ability to ribosylate proteins after DNA damage is  badly hampered (von Kobbe, et al., 2003). The conclusions of all three experiments are not concrete. More studies and experiments  get hold of to be done to  to the full  get a line Werner syndrome. Faraghers experiment sought to  try that the gene responsible for WS was  real a gene which controlled senescence and he was right. He  cerebrate that WS gene is a counter that modulates the frequency at which cells in culture leave the cell cycle (Faragher, et al., 1993).Still, there is   excess   much research to be done to understand all aspects of the gene. Kyngs experiment focused  in the main on the types of genes which were affected, but more research is needed  forward his findings could be considered definite.                                        If you want to get a full essay, order it on our website: 
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