Monday, 28 January 2013

Disorder at Work


                                                          Disorder at Work
Richard Kriwacki refused to give up on his protein. He had tried again and again to determine its three-dimensional shape, but in every experiment, the protein looked no more structured than a piece of cooked spaghetti.
Normally, this lack of form would be a sign that the protein had been destroyed, yet Kriwacki knew for a fact it could still do its job in controlling cell division. While discussing the conundrum with his adviser in the atrium of their La Jolla, Calif., lab, insight dawned: Maybe the floppy protein didn’t take shape until it attached to another protein. Kriwacki raced off to do yet another experiment, this time combining his protein, p21, with a partner. Sure enough, Kriwacki got what he was looking for. Once joined, a seemingly ruined mess gave way to a neatly folded structure. The finding defied a foundational dogma of biology, that structure determines function.
Nearly everything the human body does, from shuttling oxygen through the bloodstream to digesting a meal, relies on proteins. These biological workhorses are composed of chains of molecules called amino acids. Whenever a chain is made, conventional scientific wisdom says, electrical forces cause it to immediately bend into helical ribbons and tight zigzags, which twist further into even more defined three-dimensional forms. The resulting shape determines what other molecular players the protein can bind to and thus what it can accomplish in a cell. Unfolded proteins were thought to result only from intolerable conditions that render a protein useless, such as extreme heat or acidity.
But since around the time of Kriwacki’s discovery more than 15 years ago, disorder has surfaced as a key player in the protein world. “Intrinsically disordered proteins,” or IDPs, turn out to play vital parts in controlling cellular processes. More than one-third of all human proteins, in fact, may be partially or completely disordered in structure, floating around like strands of wet noodles. “The roles that disordered regions can play are quite diverse,” says Kriwacki, now at St. Jude Children’s Research Hospital in Memphis, Tenn.
 To better understand how something so flexible can be functional, researchers are now taking a closer look at how the disordered proteins interact with other proteins. The disordered dissidents can behave as switches, quickly turning cellular processes on or off in response to changing conditions, or as shape-shifting ensembles that integrate multiple signals before telling a cell to get a job done. Studying the interactions of intrinsically disordered proteins may even yield insight into certain diseases and lead to new treatments.
 http://www.sciencenews.org

How air become petrol?




   
 
   

Relatoion Between human and horse

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Monday, 21 January 2013

Educational Poetry

Honton pay hay lipstick or naina kajal say lais
Neutralization take place when acid react with base
us ka bhai nay mujhay bohat peeta
sin theta our cos theta is equal to tan theta
kutta bhi hopta hay apni gali may king
noun is the name of person place or thing
us ko na rahi meray pyar ki qadar
two parallel cannot intersect to each other
 
 

Life vs death essay



LIFE VS DEATH
Life and death are the realities which cannot be denied. Modern changes gaze away from this most important issue. Many people think that the life is something to be feared; they also noted that the death is just like absence of life death has even come to be considering somehow unnatural. Somehow they are some similarities and many differences between life and death.
        The similarities between life and death are that both hold the element of mystery. People are afraid of both of them but in different ways. Both are realities which definitely happen. Moreover one of the major similarities between both of them is that without each other they cannot exist.
        On the other hand there are many differences between them. One of the major differences is that when a person born he or she cries while all other smiles but when he or she died he or she remains silent but everyone cries.
         Both are different states of existence in which the present existence prepare one for the life to come for the life here after. Both life and death are similar and different in their in states and to me are very important

reading islamic book