Randy Schekman, one of the recipients of the 2013 Nobel Prize for Medicine, told AFP Monday that he received the news with a mixture of "disbelief and joy."
Schekman, 64, won the world's most prestigious academic award along with two other researchers for work that has "solved the mystery of how the cell organises its transport system," the Nobel Committee said.
"My reaction when I heard about it was one of disbelief and joy," said Schekman, a professor of molecular and cell biology at the University of California at Berkeley.
He said that receiving the Nobel Prize, along with fellow American James Rothman and German-born Thomas Suedhof, was the culmination of nearly four decades of dedicated work.
"I've been at it for 37 years, and Rothman for a similar period of time," he said. "We realised 25 years ago that we were working on the same subject."
At the center of Schekman's research are vesicles, small packages that transport molecules around the cell.
Schekman discovered a set of genes that were required for vesicle traffic, using yeast as a model system when he began his research in the 1970s.
"Ordinary people can benefit from this basic research into how cells work, which has unexpected and dramatic implications for their own lives," he said.
According to the Nobel Committee, the research gives valuable insights into disease processes.
"Defective vesicle transport occurs in a variety of diseases, including a number of neurological and immunological disorders, as well as in diabetes," the committee said in its press release.
Schekman told AFP that even though his life had changed as of Monday, he was determined to carry on his research as before.
"The science will go on. We're very excited about what we're doing in our lab," he said.
His immediate plans were straightforward: "When the phones stop ringing, I plan to take a shower and get a second cup of coffee," he said.
He added it was "too early to say" what he would do with the prize money.
The three laureates will share equally the prize sum of eight million Swedish kronor ($1.25 million, 925,000 euros).