Rosalind Franklin: Beyond the Double Helix

(Inside Science)-If you’ve heard the name Rosalind Franklin, you’ve probably heard the names of James Watson and Francis Crick. Watson and Crick form the most famous duo known for understanding the shape of the spiral staircase of DNA, and Franklin’s public image is closely linked to the story of how everything happened. ..

In the portrayal of the story Watson published in the 1968 book The Double Helix, Franklin was warlike, reluctant to cooperate, and struggled to interpret her own data. Watson commented on his appearance and clothing and gave him a nickname (Rosy) that he had never used. The account triggered a backlash, and in many subsequent stories, Franklin became an unjustified heroine. The data was stolen and the intelligence was suppressed by a patriarchal man. (Watson’s epilogue to “The Double Helix” acknowledged Franklin’s early impressions in his book, was often wrong, and points to her many achievements.)

Franklin’s second biographer, Brenda Maddox, thought both stories were offensive to her subject. In 2003 paper In science magazines NatureMaddox wrote that Franklin’s story as a feminist icon was a powerful myth that grew “until obscured.” [Franklin’s] As a scientist and as an individual, he has intellectual power and independence. “100^Th The anniversary of Franklin’s birth on July 25th of this year provides an opportunity to recall all of her scientific contributions.

Indeed, Franklin played a crucial role in discovering the structure of DNA in the early 1950s. Watson and Crick’s ideas were guided by meticulous photographs and calculations made by Franklin and graduate student Raymond Gosling, and were probably shown to Watson and Crick without Franklin’s knowledge. play, Lap battle, Commemorative coins, And many written explanations focus on the particular part of this data, the famous “Photo 51”. Watson wrote in his book: “When I look at the photo, my mouth opens and a pulse begins to sound… The black cross of reflexes that dominates the image arises only from the helical structure… Radiographs show some important spirals. I gave it a parameter.”

In fact, Watson probably wrote extensively about the race to discover the structure of his own “Eureka!” DNA, and Matthew Cobb, a geneticist at the University of Manchester in the UK, is the moment for a good story. said.

Photo 51 Photographed by directing a beam of X-rays onto a thin strand of DNA. When the X-rays encountered electrons within the atoms of DNA, they were redirected at a specific angle, forming a pattern of bright and dark patches on the X-ray film. To understand X-ray images like Photo 51, scientists need to perform a number of mathematical calculations to reconstruct the path taken by X-rays and the way they interfere with each other.

When Watson turned to Photo 51, the researchers did a thorough analysis and knew that a corkscrew-like structure called a helix produced a cross in such an x-ray image. .. You can use the spacing between the crosses to calculate how tight the helix is. But earlier experiments have led many scientists to believe that DNA is a helix, Cobb said. Important mysteries, such as the number of strands and how the strands were combined, remained unsolved.

According to Cobb, this is part of Franklin’s numerical data and is likely to play a larger role than a single image. As Franklin left King’s College in London and is preparing to proceed with other studies at Burke Beck College, she wrote it in a report presented to Watson and Crick. Franklin calculated important details that can be interpreted in terms of atomic group spacing and symmetry in DNA samples.

Crick, when looking at Franklin’s numbers, realized that the symmetry he described could be achieved by two helical strands running in opposite directions. The mind of Crick was prepared for this insight as he was working on a mathematical framework for interpreting the data generated by taking X-ray images of helical molecules as part of his. Thesis, Cobb said. Franklin continued to analyze the data until he left Kinglin, and working on the notebook revealed that she was approaching the correct structure. Nature In 1968 I looked up her work on DNA. Frank pointed out that Franklin had a philosophical difference from Watson and Crick. She liked collecting data and analyzing it. Watson and Crick led the modeling, even though early data were still populated. I was not afraid to suggest a model that failed under scrutiny before it finally became correct. Initially, Franklin wasn’t as obsessed with DNA as Watson, according to Cobb. According to Mr. Cobb, the fact that we are still very focused on this aspect of her life is proof that Watson is still shaping the idea of ​​Franklin.

The whole DNA story was a short two-year dawn of Franklin’s prolific scientific career, shortened when he died of ovarian cancer at the age of 37 in 1958. Franklin started studying coal and finished researching viruses. Her measurements of the size and shape of small holes in different types of coal, and how they burn, have influenced a wide range of technologies, from gas masks to smelting plants. After moving away from DNA, Franklin and her colleagues understood the structure of the tobacco mosaic virus that infects tobacco plants. She studied other plant viruses and at the time of her death she turned her attention to polio.

Her London tombstone inscription says, “Her research and discovery of the virus is still of lasting benefit to humanity.”

“She died proud of her worldwide fame in the study of coal, carbon and viruses,” Maddox wrote to her. Nature essay. “I would never have imagined that she would be remembered as the heroine under the edge of DNA, given the determination to avoid fancy speculation.”

Science is an effort that Franklin has been devoted to since his youth and is not in line with the truth, but his zigzags and zags are usually added together to make the right overall move. Perhaps Rosalind Franklin’s story will follow a similar path, eventually leading to a story that captures her scientific life more in its beautiful richness.