Experimenters have recently found that genes–whereby they mean particular sequences of DNA–can “find” one another without the intervention of proteins or other factors. It appears to be strictly an effect caused by electrical charges along the DNA strand; the longer the ‘gene’ (that is, sequence length), the greater theapparent ease in ‘finding’ one another. The experimenters feel that this finding is a help for figuring out what happens during homologous recombination.
Here’s part of what they say: The researchers observed the behaviour of fluorescently tagged DNA molecules in a pure solution. They found that DNA molecules with identical patterns of chemical bases were approximately twice as likely to gather together than DNA molecules with different sequences.
Professor Alexei Kornyshev from Imperial College London, one of the study’s authors, explains the significance of the team’s results: ‘Seeing these identical DNA molecules seeking each other out in a crowd, without any external help, is very exciting indeed. This could provide a driving force for similar genes to begin the complex process of recombination without the help of proteins or other biological factors. . . .’
The article from ScienceDaily is here.
I have an OOL question: This study strongly suggests that similar DNA sequences have a preferential attraction for one another. And the longer the similar sequence, the greater the attraction. If that is the case, then, if a particular ‘gene’ began to ‘replicate’, wouldn’t the replicated ‘genes’ congeal together?
If this is true, then it would seem that the DNA would, per force, need to be isolated from other similarly sequenced DNA. And this, in turn, implies some kind of membran surface. The dilemna that I see, is that in order to replicate the DNA sequence needs a membrane-like environment; but doesn’t his mean that the membrane must also replicate along with the DNA so as to keep the two ‘genes’ apart. Yet, unless directed by a whole host of ‘genes’, why, and how, would the membrane know to divide? So, in a free solution, how do you keep replicated DNA from congealing? Seems like this is just one more headache to resolve for those who think the first cell/first DNA just happened.