New advances in molecular biology: smart genes
New advances in molecular biology: smart genes
Author: Mariano Artigas
Published in: Aceprensa, 161/91
Date of publication: 4 December 1991
Molecular biology is advancing at an unstoppable pace, bringing before our eyes a fascinating world of microscopic mechanisms that function with astonishing precision. The most recent advances lead biologists to speak of intelligent functioning.
Physics was the first discipline to establish itself as a rigorous science in the modern sense. From the 17th century until well into the 20th century, physics was the paradigm of scientific thought and provided the instructions scientific picture of nature.
In recent decades the status has changed. It is not that physics has lost its importance; it is still the basic discipline because it studies the laws at the fundamental level of nature. But biology is achieving spectacular successes that reveal a much richer organisation of nature than that of physics. This is logical. Living things are the most sophisticated things in the realm of nature.
The development of the organisms
Tim Beardsley recently published a paper in the journal research and Science, article graduate Smart genes *(1). The problem that arises is that of differentiation: how do you explain that very similar genes produce very different cells?
As the fertilised egg develops, different cells are produced and take their place and carry out their specific functions. Beardsley sums it up in a nutshell: "During the development of an organism, cells move, migrate, follow complex strategies, change their shape and eventually associate to form specialised tissues. A human being, for example, has more than 250 different types of cells, and each must be and function in the right place. (Liver cells would be useless in the brain). ) Yet they all carry the same genes in their DNA.
We have known for a long time that genes are switched on and off in these processes. Now we are beginning to understand the mechanisms of the process, i.e. how the activity of genes is harmonised so that at the right time the different cells are formed and perform their function in the right place. Beardsley says: "Hundreds of experiments show that control of the expression of most genes in an organism is almost always achieved through the regulation of transcription, a process that copies the information Genetics contained in DNA into RNA, the molecules used to make the millions of proteins that make one cell markedly different from another.
Beardsley goes on to point out that, according to Eric H. Davidson of high school of California Technology, "the main teaching of molecular biology in the last 20 years is the control of gene expression through transcriptional regulation".
Davidson, who has been one of the protagonists of these advances, speaks in this context of smart genes and the brain of the smart gene. This brain is a complicated aggregate of proteins, a kind of computer "where signals are combined and the decision is made whether or not to activate a gene".
Beardsley stresses that the basic mechanisms of these processes appear to be the same in all multicellular organisms, so that "the smart gene may be one of the universal features on which the processes of embryonic development depend".
The terminology used is striking. It is clearly anthropomorphic language, as it attributes intelligence, the ability to integrate information and decision-making capacity to biochemical entities. Scientists are usually reluctant to use such language unless it is absolutely necessary. Apparently, in this case, it is.
Indeed, Beardsley later picks up on the following statement by Jacob and Monod, who shared the 1965 Nobel Prize in Medicine award for their contributions to molecular biology: "the genome contains not only a series of blueprints, but a whole coordinated programme of protein synthesis and means of controlling its execution". Programme and control are also anthropomorphic terms, as they suggest the existence of someone who programmes and controls.
But this would be more than anthropomorphism, because we have not programmed the genes, nor do we control them. Therefore, it seems that such programming can only be attributed to someone who is above us and above nature; moreover, to someone who is the author of nature, i.e. God.
However, neither Jacob nor Monod shared this idea. François Jacob wrote a book graduate The Logic of the Living, in which he contrasted the scientific with the religious. Jacques Monod published his lectures from the 1969-1970 course at high school in France in his book Chance and Necessity, which became world famous. As the degree scroll of his book puts it, Monod claimed that natural phenomena are explained by a combination of chance and necessity. Science would leave no room for higher plans.
The problem is an old one. Certainly, there are laws of nature and scientists are working to understand them, with increasing success. In this sense, it is not a question of substituting scientific explanations or natural laws for divine action. Nature has an autonomy of its own: ordinary experience testifies to this, and science leads to a much deeper understanding of the natural laws knowledge . No one in their right mind would put divine action on the same level as the action of stones or electrons. The problem is that natural laws, especially if it is a specific coordination within an overall programme, seem to demand an author. Programming demands a programmer.
This requirement becomes more evident the further science advances. And it is precisely molecular biology is the scientific discipline that highlights this most clearly, through the idea of information.
Biology and information
At the level of biology, concepts from cybernetics and information theory are used.
One of the most remarkable features of the organisation of the subject is precisely that it takes place through the transfer of information between beings that do not have knowledge. The atoms, so to speak, know which energy states can be occupied by electrons and which cannot. Genes contain the necessary instructions for the organism's development , so that the production of proteins, the training of new organs and so many other vital processes are directed by this information.
Beardsley writes at article that "cells in a complex organism need to know where they are located to decide which genes to express. And they should also be able to respond to emergency situations, such as aggression or the sudden presence of a hormone. Of course, they need to know a lot of things.
Molecular biology studies the basic mechanisms of the organisation of living organisms. Organisation refers to systems whose components perform different functions within an organised whole. In order to assemble joint actions, it is necessary to possess and transmit information.
However, it is not easy to determine exactly what is meant by information. The concept of information varies considerably from one author to another. In any case, information is always information for a receiver. It does not have an absolute meaning. For information to exist there must be a message, a receiver, and a system of reference letter about which the message informs the receiver. All this presents no conceptual difficulties if the receiver is a being endowed with knowledge. But what sense can it make in other cases?
The B fact is that nature has been using extremely subtle means of information, coding, interpretation and transmission long before we discovered them, and often more effectively. Advances in molecular biology bear this out.
It is difficult not to be astonished by this. Of course, reflection on this fact leads to reasoning that is sometimes not straightforward. But one thing seems clear, and that is the following. If ancient authors, such as St. Thomas Aquinas, who saw in nature a kind of unconscious intelligence that necessarily refers to an intelligent First Cause (a creative and ordering God), were alive today, they would look with great satisfaction at the current knowledge of molecular biology.