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Proteins essential to species differentiation- evolved or designed?


Researchers have discovered two proteins essential for reproductive cells to latch onto each other and then to fuse. Changing at least one of these proteins appears to prevent species from interbreeding. This appears to open up a way to stop malaria. A new species would appear to require at least two changed genes, one for the protein change and the other for the matching protein docking change. What is the probability of these simultaneous changes occurring by random mutation & natural selection – versus – this being a key/lock design with complex specified information? Such simultaneous changes appear to be pushing Behe’s limits of Darwinism. See Edge of Evolution
Gene blocking could help quash malaria
April 1, 2008

International investigations of an organism that one Univ. of Texas Southwestern Medical Center researcher calls a “silly little green scum” have led to key insights into the basic mechanisms of reproduction.

The findings may help explain why species can almost never interbreed, and also point to a possible way to thwart the spread of malaria, a disease that kills about 1 million people each year, primarily children in sub-Saharan Africa.

In a study to be published in the April 14 issue of the journal Genes and Development, and available now, researchers from UT Southwestern have found that sexual reproduction begins with two genetically different steps: First, two reproductive cells must latch onto each other with one protein, and secondly, they must fuse their membranes to form a single cell using a different protein.

The UT Southwestern scientists collaborated with malaria experts at Imperial College London and found that the parasite causing the disease also uses this two-step process. When they blocked “male” and “female” malarial cells from fusing, spread of the mosquito-borne disease was stopped.

See full article

See paper:
The conserved plant sterility gene HAP2 functions after attachment of fusogenic membranes in Chlamydomonas and Plasmodium gametes
Yanjie Liu1,7,et al.
March 26, 2008, Genes and Development, DOI: 10.1101/gad.1656508

. . .Membrane dye experiments show that HAP2 is essential for membrane merger. Thus, in two distantly related eukaryotes, species-limited proteins govern access to a conserved protein essential for membrane fusion. . . .

DHL, Maybe you could get Dr. Behe or Dr. Wells to comment on this. DeepDesign
From Janjie's et al. abstract: Fact 1:
"HAP2 is essential for membrane merger"
Fact 2:
"yet Chlamydomonas minus and Plasmodium hap2 male gametes retain the ability, using other, species-limited proteins, to form tight prefusion membrane attachments with their respective gamete partners."
From these facts and the ID paradigm, following are two proposed ID hypothesis to pursue (as posited by a design engineer): ID hypothesis 1: The membrane merger including HAP2 essential for such "male"-"female" cell merger are irreducibly complex. ID hypothesis 2: This "male"-"female"protein & docking site are part of a species specific reproduction - barrier system that is a species specific irreducibly complex system. Submitted for further evidence to support and/or refine these hypotheses. DLH
This does look promising. DeepDesign
Calling on biochemists to verify or clarify this interpretation. DLH
Did I understood correctly? This is application of predictions of Behes Edge of Evolution in practical medicine? Shazard

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