Nature's Gift to Neuroscience

A Tribute to Sydney Brenner and John Sulston

Chun-Fang Wu, Joy Alcedo

• Publisher: CRC Press
• Year: 2022
• ISBN:
  9781000566444
• Edition: 1
• Topic: Biological Sciences
• Subtopic: Neuroscience
• Index: Biological Sciences

In the 1960s, Sydney Brenner proposed to use the nematode worm Caenorhabditis elegans to discover the control mechanisms of animal development and to reveal how a small number of neurons generate different behaviours, giving birth to a vibrant community that uses this animal model for their studies. Brenner was aided in his aim by John Sulston, who mapped the C. elegans cell lineages – from a single cell to the multicellular adult – which transformed the field of developmental biology.

As a tribute to these two men, this book captures the perspectives of some of the early pioneers of the worm community, from Martin Chalfie, Robert Waterston and Donald Moerman to Catherine Rankin, Antony Stretton and John White. It also includes contributions from subsequent generations of the community, who explore the development and function of the C. elegans nervous system. This book features how this animal has become one of the best models for elucidating the biology of different sensory modalities and their complex behavioural outputs, or how this animal's survival strategies have contributed to our understanding of ageing and neurodegeneration. Thus, this volume documents the development of the C. elegans neuroscience field, from infancy to maturity.

The chapters in this book were originally published as a special issue of the Journal of Neurogenetics.

Part I The early years of C. elegans neurogenetics

My life with Sydney, 1961–1971

Antony O. W. Stretton

Abstract

During the 1961–1971 decade, Sydney Brenner made several significant contributions to molecular biology—showing that the genetic code is a triplet code; discovery of messenger RNA; colinearity of gene and protein; decoding of chain terminating codons; and then an important transition: the development of the nematode Caenorhabditis elegans into the model eucaryote genetic system that has permeated the whole of recent biology.

What a joy, what a privilege, to have worked with Sydney Brenner at the Laboratory of Molecular Biology (LMB) for 10 years, between 1961 and 1971 (Figure 1). I worked with him on colinearity and decoding the amber chain termination codon, and then switched to nematodes and neurobiology. He recruited me because he was looking for a protein chemist to help with the colinearity project, which had been one of his major obsessions for years. He had been the internal examiner for my Cambridge PhD oral defense in 1960. I had worked on amino acid sequences in hemoglobin; I guess he must have liked my work, and he also figured (rightly) that I was unlikely to give him any lip. In what follows, I will try to bring out what struck me most about the character of this brilliant, complicated, irreverent, and hilarious man, and the original science he pioneered during those 10 years. I include some autobiography for background.

Figure 1. Sydney as I knew him in the 1960s (MRC Laboratory of Molecular Biology).

In fact, I first met Sydney in 1957, when I was a PhD student with Vernon Ingram, an organic chemist in the MRC Unit for the Study of Molecular Structure of Biological Systems, housed in the Cavendish Laboratory, the Physics Department of Cambridge University. Typically, MRC Units are small, highly specialized groups, and this one, with Max Perutz as its head, was focused on solving the structure of complicated molecules like proteins by X-ray crystallography; it was housed in the Cavendish Laboratory because William Bragg, the famous X-ray crystallographer, believed in Max. The Unit included John Kendrew and Hugh Huxley, who was Kendrew’s PhD student; Francis Crick was another early member. Soon Max realized he needed chemists to make heavy atom derivatives of hemoglobin to help with the ‘phase problem’ in X-ray crystallography, and Vernon was one of these. Vernon then went on to do his famous experiments showing that sickle cell hemoglobin differed from normal hemoglobin by a single amino acid substitution (Ingram, 1956), and he became known as the ‘father of molecular medicine’.

My initial combined lab and office space was a 3′ X 3′ section of a lab bench; a little later in the year, the entire unit moved into The Hut (Figure 2), an asbestos structure in the courtyard next to the bike racks, and I got half a lab bench to myself. The X-ray machines used by Max Perutz, John Kendrew and their colleagues stayed in the basement of the Cavendish, but they all had their offices in the Hut. Francis Crick was also a member of the lab, and the scientific interests of the group continued to broaden, largely due to Crick’s interest in DNA and the genetic code. Sydney had joined him in 1956. It was an amazingly talented group!

Figure 2. The Hut (Photo credit Hans Boye; MRC Laboratory of Molecular Biology).

Every morning at 11 am, the whole unit met for coffee (excellent coffee made by Leslie Barnett) in the entrance lobby. I was spellbound by Francis’ and Sydney’s brilliance. My training had been in organic chemistry, and I had never learned genetics. My closest contact with this new world had been Professor Sir Alexander Todd’s superb lectures on the chemical structure of nucleic acids, but that was pure chemistry, with no reference to the importance of the nucleotide sequence. I had a very steep learning curve, and I kept my mouth shut for over a year.

Francis and Jim Watson had recently (Watson & Crick, 1953) published their seminal paper on DNA structure, and Francis was crystallizing his thoughts on the genetic code (see his glorious paper entitled ‘On Protein Synthesis’ (Crick, 1958)). At the MRC Unit, most of the coffee-time talk was about the Central Dogma and the genetic code. That was the influence that had taken Vernon to sickle cell hemoglobin. In the autumn of 1958, Vernon moved to the Biology Department at MIT, and took me with him to finish my PhD research.

1957 was the year when Sydney and Francis had invited a bunch of illustrious American visitors, and they were going to solve the colinearity problem. There was Seymour Benzer, who had just analyzed a huge number of mutations of the rII gene of bacteriophage T4, showing that they mapped as a linear structure, just like DNA and proteins (Benzer, 1961). But did the sequences really correspond? Were the mutations in DNA arranged in the same order as the amino acid changes they produced in the protein? That was the colinearity problem. No-one had yet identified the rII protein, and it seemed to be synthesized at low levels, making it hard to isolate in large enough amounts for protein chemistry. So there was a determined search for the right gene-protein pair. The issue of colinearity seems so clear and obvious these days, but its demonstration was a crucial test of the growing construct we now call molecular biology. Back then it was not the only possibility—for example, the work of Perutz and Kendrew reinforced the prevalent idea that proteins were intricate three-dimensional structures; the transition from a one-dimensional polypeptide chain to a complicated three-dimensional structure was not obvious. Maybe that is what the genes controlled. Anfinsen and Haber showed that RNase A could be reduced to break the disulfide bonds, then completely unfolded in urea and when the urea was removed it refolded, the disulfide bonds reformed, and it regained its full enzymatic activity (Anfinsen & Haber, 1961). This was taken as a ‘don’t worry’ demonstration that the amino acid sequence itself can generate the right folding, but is this a fluke—what about other, larger proteins?

Seymour brought his graduate student Sewell Champe. Seymour also brought his wife, Dotty. What a lovely, sweet woman. She and Seymour were crazily in love, and everyone loved them for it. George Streisinger, another phage geneticist, came with his wife Lotte, a superb potter; they too were a wonderful example of a good marriage. Mahlon Hoagland, who had worked with Paul Zamecnik on the role of soluble RNA (tRNA) in protein synthesis was there. Paul Doty, the DNA physical chemist from Harvard, was there too. Much of the year was spent in talk, searching for the right protein with which to map the results of mutation. I remember Seymour eventually becoming very impatient with the (to him) distorted ratio of talk to action, and he started to work with Vernon on another abnormal hemoglobin, hemoglobin D (Benzer, Ingram, & Lehmann, 1958). He wanted, at least, to learn Vernon’s techniques in protein chemistry. The year ended without colinearity being solved. But I was able to observe a pretty wide variety of intellectual styles of these very successful scientists. There are many ‘right’ styles, and that was a useful lesson for a first-year graduate student. I was very lucky!

During that year, I did not get to know Sydney as well as I did later, but it was obvious that he was absolutely brilliant. I also began to see that he had a fantastic sense of humor. At one big lab party at his house, he was talking with Ann Cullis, a young, elegant postgraduate physicist who was working with Max as his assistant, and I overheard her saying to Sydney ‘I’m sorry, I’m no good at small talk’ and Sydney replied ‘Alright then, let’s talk big!’ I think he swiped that line from the Marx Brothers, like his reply to the question ‘Do you have a rubber band, please?’, ‘Sorry, no. But I do have a string orchestra.’ At that time, Sydney was a heavy smoker, and at each pull he puffed out his cheeks like Zephyr in Botticelli’s ‘Birth of Venus’ and then took the smoke deep into his lungs. Fascinating! Was he deliberately increasing the absorptive surface area to get a better nicotine high? I should have asked him.

With Vernon I worked on sequencing the delta chain of human hemoglobin A₂, a minor normal hemoglobin controlled by a different gene from the major hemoglobin, hemoglobin A (Ingram & Stretton, 1961). After my PhD, I stayed at MIT for a year, and was appointed as an Instructor, so I had to teach. I found that I liked it, which was a surprise, since at the MRC lab, teaching and those who did it were regarded as rather despicable lower forms of life and their commitment to science was held in doubt. Talk about an attitude!

In 1961 I went back to Cambridge to join Sydney, and I occupied my old bench in the Hut! Already the new Hills Road lab in the Addenbrooke’s Hospital complex was under construction, and we moved in during the Spring of 1962 (Figure 3). It was now named the Laboratory of Molecular Biology and besides the X-ray crystallographers and the molecular geneticists (Crick and Brenner), the new group included Fred Sanger and his associates who moved from the Biochemistry Department, and Hugh Huxley. These were the members of the Governing Board (Figure 4); Max was Chairman of the Board, and there were the three Divisions, Structural Studies (headed by Kendrew), Molecular Genetics (Crick and Brenner) and Protein Chemistry (Sanger). Each division had many junior appointees, and I was one of them.

Figure 3. The new Laboratory of Molecular Biology ca. 1962 (MRC Laboratory of Molecular Biology).

Figure 4. The Governing Board of the LMB in 1968 (MRC Laboratory of Molecular Biology). Left to right: Hugh Huxley, John Kendrew, Max Perutz, Francis Crick, Fred Sanger, Sydney Brenner.

I had a bay (two benches) in a lab next to Sydney’s, and I was incredibly lucky to have two technicians assigned to me, Rita Fishpool and Eileen Southgate, both of whom had been trained by Vernon, so they knew all his peptide chemistry techniques. They were both very intelligent and they liked to work hard, and they picked up new techniques very quickly. That was an era when technicians were a separate class—their names did not appear as authors on papers, and they were not expected to participate in scientific discussions. At the Cavendish, they had a separate canteen from the faculty and students. This was the quintessence of the English class system. In the new lab, there was only one canteen, definitely a step in the right direction, but still the technicians usually chose to sit at separate tables. The whole system was in transition, and Rita and Eileen both agreed with me when I said that if they had been born a generation later they would have attended university instead of technical college and would almost certainly have gone on to earn PhDs. They were really good!

Having been in the States for three years, I saw the class system from the outside for the first time and saw it for what it was—EVIL! I was born in Rugby, and at age 13 went to Rugby School, a top English public school, as a day boy, and what a weird experience that was. We ‘town boys’ were a 10% minority, and most of the rest of the boys were upper middle class or better—they had to be for their parents to afford the fees. We were not. Plus, we came to the school speaking with the local accent—Roogbee — but that soon got knocked out of us. Almost all the boarders were embryonic Tories, and most of them truly despised the town boys for what we were. This was the first time I had experienced prejudice, although from my reading I conclude that it is nothing, nothing at all, like what too many people do to people with different colored skin. But it was not all bad: we were lucky in that ...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Citation Information
• Notes on Contributors
• Introduction: Nature’s gift to neuroscience
• Part I The early years of C. elegans neurogenetics
• Part II Nervous system development
• Part III From inputs to outputs
• Part IV Social and sexual behaviors
• Part V Quiescence and sleep
• Part VI Survival, aging and disease
• Part VII Worm photo and art gallery
• Index