Nuclear Gates

Nuclear Gates

The cell is a marvel of microengineering. It is the basic unit of life and contains the functional pieces that make life possible. Cells perform replication, nutrient uptake and digestion, and manufacture proteins.  One of their most essential functions is to both replicate the DNA of the cell and produce proteins to keep the cell running.  A recent study out of the California Institute of Technology has discovered the mechanism the cell uses to permit information to travel from the nucleus into the cytoplasm for protein synthesis.  These mechanisms are the focus of today’s article.

The cell is divided into three main parts. The first part is the nucleus, which stores genetic information. The second is the cytoplasm, where protein synthesis and nutrient digestion takes place. The third is the cell wall or cell membrane, which serves as a defense and doorway to the cell. The nucleus, with its vital stores of DNA information, is essentially a cell within a cell. It has its own membrane that separates it from the rest of the cell. Moving between the cytoplasm and the nucleus require passing through one of several types of molecular gates that guard transport between the two. One of these gates is called the nuclear pore complex. This is abbreviated to NPC, which anyone who plays video games can relate to with a different meaning. The nuclear pore complexes are big enough in microscopic cellular terms, to permit mRNA to pass out of the nucleus, and into the cytoplasm.  This is a key ability becaue mRNA is responsible for carrying the information for the synthesis of proteins.  This information needs to pass into the cytoplasm in order to create the proteins essential for the cell to survive.

While the nuclear pore complexes are large enough to admit an mRNA strand, there is a lot more to it than that.  Access to the nuclear pore complex can only be obtained through a special protein marker, called a nuclear export factor. The nuclear export factor acts as the key to unlock the nuclear pore complex. The problem is, mRNA is not made with a nuclear export factor attached. It must acquire one as it travels in the nucleus. Fortunately, they are availble in the nucleus and the mRNA is able to acquire them. When the mRNA attempts to leave the nucleus through the nuclear pore complex, the NPC will not let it pass unless it has a nuclear export factor. The researchers used the anaology of a ticket. To pass through the NPC, mRNA must present its ticket, in this case the nuclear export factor.  However, it cannot keep the nuclear export factor forever. If it did, the mRNA might accidentally go back into the nucleus through another NPC where it would be completely useless. Thus at the end of the NPC, the mRNA gives up its nuclear export factor.  It does this because of several proteins working together to strip the nuclear exon factor from the mRNA. This does not adversely affect the mRNA at all and it will continue on in the cytoplasm until it meets a ribosome and is transcribed.

The above paragraph has some sizeable implications to the theories of origins. For example, without the NPC and nuclear export factor, mRNA, presuming it already existed, would be unable to exit the nucleus. This would mean no protein production for the cell, something that quickly would kill it. Even supposing that the NPC and the nuclear export factor both existed, there is still the sizeable problem of removing the nuclear export factor.  If it is not removed, the mRNA stands a sizeable chance or reentering the nucleus and doing nothing to help create new proteins. Removing it requires a couple of separate proteins. Thus the NPC, nuclear export factor, and the multiple proteins required to remove the nuclear export factors must all have been in place at the same time as the cell developed replication, or the replication process does not work.

Evolution demmands a slow, gradual development in response to enviromental pressures. Yet there is no way the NPC, nuclear export proteins, and mRNA could possibly have developed gradually. They all had to exist simulataneously or the replication would not work.  This completely undermines evolutionary thought. If this could gatekeeping process as it were could not develop gradually, then evolution fails as a theory. A far better idea is to accept that God designed the cell to operate thus when He created the world. This would have ensured that all necessary parts for the cell were present from the beginning, avoiding the need for slow gradual development that would not work.

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