Weizmann Institute researchers have made two separate discoveries that have revealed and help explain the resilience of life's most basic building blocks.
In one Weizmann Institute study, it was shown that the molecules in charge of the task of copying DNA – called DNA polymerases – are able to improvise.
When human cells wear out, other cells divide and re-divide to replace them. During this process, when the polymerases encounter damaged or foreign DNA material, the regular DNA polymerases stop working. However, the Weizmann scientists discovered, to their amazement, that in such a case, a specialized DNA polymerase jumps in to rescue the stuck replication process, and continues the copying process, inserting nonexistent genetic components in place of the foreign material.
This new insight into DNA replication and repair, Weizmann Institute spokespersons say, could assist in the diagnosis and treatment of diseases in which DNA damage is involved, such as cancer. The surprising findings appear in the Proceedings of the National Academy of Sciences (PNAS), USA. The research was carried out by Professor Zvi Livneh and Ph.D. student Ayelet Maor-Shoshani of the Biological Chemistry Department.
In a related discovery, Weizmann Institute scientists revealed a key process in the regeneration of damaged peripheral nerves (nerves in any part of the body aside from the brain and spinal cord).
In a study published in Neuron magazine, Dr. Michael Fainzilber and Ph.D. students Shlomit Hanz and Eran Perlson have now shown that a special protein is produced upon injury at the site of damage in the nerve cell's axon. Called importin beta, it normally resides far away from the axon, near the nucleus of nerve cells. The protein then binds to unidentified proteins that contain the "healing message" and the protein complex gains easy entrance to the nucleus due to the presence of importin alpha and beta.
Since the central and peripheral systems are connected to each other, the ability to transfer substances within the peripheral nervous system could one day offer a springboard from which to introduce therapeutic agents into the brain and spinal cord. Scientists have been trying to understand how nerve cells regenerate in order to better treat damage to the peripheral nervous system. In addition, knowing how these neurons regenerate could provide insights into fixing neurons in the central nervous system (where damage is irreversible).
In one Weizmann Institute study, it was shown that the molecules in charge of the task of copying DNA – called DNA polymerases – are able to improvise.
When human cells wear out, other cells divide and re-divide to replace them. During this process, when the polymerases encounter damaged or foreign DNA material, the regular DNA polymerases stop working. However, the Weizmann scientists discovered, to their amazement, that in such a case, a specialized DNA polymerase jumps in to rescue the stuck replication process, and continues the copying process, inserting nonexistent genetic components in place of the foreign material.
This new insight into DNA replication and repair, Weizmann Institute spokespersons say, could assist in the diagnosis and treatment of diseases in which DNA damage is involved, such as cancer. The surprising findings appear in the Proceedings of the National Academy of Sciences (PNAS), USA. The research was carried out by Professor Zvi Livneh and Ph.D. student Ayelet Maor-Shoshani of the Biological Chemistry Department.
In a related discovery, Weizmann Institute scientists revealed a key process in the regeneration of damaged peripheral nerves (nerves in any part of the body aside from the brain and spinal cord).
In a study published in Neuron magazine, Dr. Michael Fainzilber and Ph.D. students Shlomit Hanz and Eran Perlson have now shown that a special protein is produced upon injury at the site of damage in the nerve cell's axon. Called importin beta, it normally resides far away from the axon, near the nucleus of nerve cells. The protein then binds to unidentified proteins that contain the "healing message" and the protein complex gains easy entrance to the nucleus due to the presence of importin alpha and beta.
Since the central and peripheral systems are connected to each other, the ability to transfer substances within the peripheral nervous system could one day offer a springboard from which to introduce therapeutic agents into the brain and spinal cord. Scientists have been trying to understand how nerve cells regenerate in order to better treat damage to the peripheral nervous system. In addition, knowing how these neurons regenerate could provide insights into fixing neurons in the central nervous system (where damage is irreversible).