Dr. Sean B. Carroll

Evolutionary Origins of Novel Genes through Regulation and Modification of Cis-regulatory Elements k

Carroll SB. Evo-devo and an expanding evolutionary synthesis: a genetic theory of morphological evolution. Cell. 2008 Jul 11;134(1):25-36.

Rebeiz M, Jikomes N, Kassner VA, Carroll SB. Evolutionary origin of a novel gene expression pattern through co-option of the latent activities of existing regulatory sequences. Proc Natl Acad Sci U S A. 2011 Jun 21;108(25):10036-43.

Werner T, Koshikawa S, Williams TM, Carroll SB. Generation of a novel wing colour pattern by the Wingless morphogen. Nature. 2010 Apr 22;464(7292):1143-8.

Rebeiz M, Pool JE, Kassner VA, Aquadro CF, Carroll SB. Stepwise modification of a modular enhancer underlies adaptation in a Drosophila population. Science. 2009 Dec 18;326(5960):1663-7.

Question 1

Very briefly tell us a bit about yourself, your career path over the years, and specifically what brought you to begin working on novel genes evolution through cis-regulatory regulation and modification?

Michael Barresi

Question 2

At the end of your 2006 paper in Cell titled “Evo Devo and an Expanding Evolutionary Synthesis: A genetic theory of morphological evolution” you state that the theory of morphological evolution will have important implications for the many other disciplines, including “population genetics and paleontology”. Could you elaborate on how you see the theory being applied more broadly? Can you envision any examples where the theory’s application in other fields will in turn build upon your understanding from a developmental genetic standpoint?

Sarah Tucker

Question 3

Your papers make a compelling case for shifts in gene expression via enhancers, rather than the development of novel proteins, driving much of the evolution of complexity. It seems highly logical that is easier to change the relationship between an enhancer and a tissue-specific TF than it is to create a functional novel protein. But the system of enhancer-induced complexity requires that a certain amount of complexity already be present–it requires many existing proteins, highly organized tissues, and tissue specific TFs. The enhancer system does not seem sufficient to manufacture such complexity from scratch. Why was the evolutionary system that created that complexity not “good enough” to continue perpetuating it? Why does a spotted wing require more agile tools to build than a segmented body or a vertebrate eye?

Lydia-Rose Kesich

Question 4

In your 1999 paper you address the Cambrian explosion and mention that the change in the environment lifted certain environmental barriers which contributed to the increased rate of diversification. How do you think that current and future climate change will alter the rate of evolution?

Marika Witkus

Question 5

You have previously written a popular science book about DNA evidence for evolution, which seems to be aimed primarily at non-scientists. Do you feel that scientists are doing an adequate job of educating the public about our research? What should scientist’s role in educating the public be? How should it be done?

Lydia-Rose Kesich

Question 6

Are some regulatory sequences more susceptible or prone to co-option? Conversely, are some particularly unlikely to be co-opted into new functions? If these differences exist, what causes them?

Julia Johnstone

Question 7

Have you looked, or do you plan to look, into evolution of transcription factor regulation? It seems an important step in understanding CRE’s as CRE’s depend on transcription factors to be more efficient and to evolve new functions for the gene.

Sarah Gaffney

Question 8

In your July 2008 review article, you mention that homeobox-containing Hox genes and Hox gene clusters are present in “most animal phyla.” What are the exceptions to this rule? In these phyla, what are Hox genes replaced by?

Emily Lyons

Question 9

You mentioned that Drosophila evolved a resistance to pesticides (through transposable element sequences). Theoretically they were able to respond to this threat so rapidly because of their fast rate of reproduction, speeding up their adaptation. With the growing levels of toxicants in the environment, and our continued discovery of their adverse effects, do you think this adaptation is conferrable to the larger order species? Will the rapid onset of climate change favor only r-selected species, who have a more sensitive evolutionary response?

Claire Maesner

Question 10

What kind of research are you looking currently and in the future?

Michael Barresi