Leukemia is known as a type of cancer that attacks the blood. A recent
discovered protein is believed to provide insights into the details of
the interaction between sperm and egg. Its structure is believed to
hold the key to new treatments for the earlier mentioned condition,
leukemia. This protein structure was discovered by C.D. Stout at the
Scripps Research Institute in La Jolla, California.
Their research has proved the connection between a protein in the eggs
of a marine mollusk and the protein on the outside of human white blood
cells.
The egg protein was from the California sea snail named Aplysia
californica, an animal that is frequently used by biologists in the
process of fertilization. As we know, events occur at the molecular
level when a sperm cell joins with an egg but these events are similar
to those that are seen among the animals and humans too. The premier
event that occurs is that a flood of calcium ions is released as a
signal for the egg to begin to divide. The flood of the calcium ions is
known to be controlled by a regulatory molecule, some kind of molecular
switch, termed as a secondary messenger.
The mentioned secondary messenger is synthesized inside the egg from
the building blocks of DNA. It is known that the reaction requires a
specialized protein known as ADP ribosyl cyclase. This is the protein
that we were talking about in the beginning of our article. ADP ribosyl
cyclase is the protein that was studied by the researchers at the
Scripps. A three dimensional image was reconstructed after preparing
the crystals of the protein and after scattering x-rays off them. The
image reveals that two of the molecules combine together to create a
hole or a molecular cavity between the proteins. In these holes or
cavities, the protein traps the DNA building blocks and rearranges
their pattern of chemical bonds to synthesize the messenger.
In leukemia patients the white blood cells have a signaling protein
called CD38 that for normal cells is present only in the early stages
of the condition. It was noticed that molecule CD38 is similar to the
cyclase protein that we discussed about earlier and that is why
researchers think that CD38 molecules also pair up to create an
internal cavity. The main difference between the cyclase and CD38
protein is that CD38 has a tail reaching across the cell membrane
providing a means for it to transmit signals to inside the white cells.
Researchers do hope that drugs targeted toward the cavity in CD#* could
be useful in allowing the immune system to eliminate leukemia cells.
