David H. Fitch

Professor of Biology


Areas of Research/Interest

Evolution of development, molecular systematics, and developmental genetics of the male tail in nematodes related to C. elegans.


Using the developmental genetic model system Caenorhabditis elegans, we are characterizing genes responsible for morphogenesis, a collection of fundamental developmental mechanisms that shape and organize cells into particular forms. C. elegans is used for this study because it is complex enough to share components and mechanisms of more complex multicellular animals, but is simple enough to be described in complete terms. The structure we are using as a model for morphogenesis is the sexually dimorphic tail tip. This simple feature is constructed of only 4 cells that, in males only, fuse very late in juvenile ("larval") development and change their cellular structure and position. This results in a blunt shape (the pointy shape of the hermaphrodite tail results from lack of morphogenetic change). We've finished a complete transmission electron microscopic reconstruction of these cellular events using serial sections, providing a descriptive foundation for further functional studies. We have isolated several mutations that fail at certain steps of male tail tip morphogenesis, and are currently cloning the genes defined by these mutations to understand their molecular functions.


Figure: Model of the 4tail tip cells in a C. elegans larva (cuticle removed).

Evolutionary changes in the development of the tail tip have also occurred. Using molecular phylogenetic analysis in combination with a developmental genetic approach, we are reconstructing the developmental changes that have occurred in male tails during the evolution of family Rhabditidae (of which C. elegans is a member). So far we have found several mutations that closely mimic evolutionary changes, suggesting candidate genes that could have been involved in evolutionary changes. These investigations will provide specific information about the genes and processes conserved in morphogenetic mechanisms as well as insight into the ways that these mechanisms can change to produce variation in multicellular form.


Evolution (V23.0058) - Fall term each year
Principles of Evolution (G23.1069) - Spring term every even year
Molecular Evolution Journal Club (G23.3018) - Fall term every year

Participation in the following courses:

  • Foundations of Developmental Genetics I and II (G23.2130-31)
  • Principles of Biology I (V23.0011)
  • Molecular and Cell Biology II (V23.0022)
  • Molecular Genetics (G23.2127)
  • Advances in Biology (School of Education)


External Affiliations

Society for Molecular Biology and Evolution, Society of Systematic Biologists, Society for the Study of Evolution.


Fulbright Fellowship, Monographic Research on the Systematics of Rhabditidae (Nematoda) and Integrated Student Training in Systematics, January 16, 2000-May 15, 2000; National Science Foundation CAREER Award, IBN-9506844, Genetic and Developmental Mechanisms of a Morphogenetic Program, August 17, 1995-August 16, 2000; Whitehead Fellowship for Junior Faculty in Biomedical or Biological Sciences, Phylogenetic Analysis of Morphogenesis in a Developmental Genetic Model at the Cellular and Ultrastructural Levels, September 1, 1997-August 31, 1999; National Institutes of Health Postdoctoral Fellowship, GM13652, Comparative Genetic Analysis of Nematode Development, February 1, 1990-January 31, 1993.


Makorin ortholog LEP-2 regulates LIN-28 stability to promote the juvenile-to-adult transition in Caenorhabditis elegans.
Development (2016 Mar 01) PMC4813343 free full-text archive
Herrera RA, Kiontke K, Fitch DH

Comparative validation of the D. melanogaster modENCODE transcriptome annotation.
Genome Res (2014 Jul) PMC4079975 free full-text archive
Chen ZX, Sturgill D, Qu J, Jiang H, Park S, Boley N, Suzuki AM, Fletcher AR, Plachetzki DC, FitzGerald PC, Artieri CG, Atallah J, Barmina O, Brown JB, Blankenburg KP, Clough E, Dasgupta A, Gubbala S, Han Y, Jayaseelan JC, Kalra D, Kim YA, Kovar CL, Lee SL, Li M, Malley JD, Malone JH, Mathew T, Mattiuzzo NR, Munidasa M, Muzny DM, Ongeri F, Perales L, Przytycka TM, Pu LL, Robinson G, Thornton RL, Saada N, Scherer SE, Smith HE, Vinson C, Warner CB, Worley KC, Wu YQ, Zou X, Cherbas P, Kellis M, Eisen MB, Piano F, Kionte K, Fitch DH, Sternberg PW, Cutter AD, Duff MO, Hoskins RA, Graveley BR, Gibbs RA, Bickel PJ, Kopp A, Carninci P, Celniker SE, Oliver B, Richards S

Curr Biol (2013 Oct 07) PMID: 24112976
Kiontke K, Fitch DH

A phylogeny and molecular barcodes for Caenorhabditis, with numerous new species from rotting fruits.
BMC Evol Biol (2011 Nov 21) PMC3277298 free full-text archive
Kiontke KC, Felix MA, Ailion M, Rockman MV, Braendle C, Penigault JB, Fitch DH

Overlap extension PCR: an efficient method for transgene construction.
Methods Mol Biol (2011) PMID: 22065455
Nelson MD, Fitch DH

In: Riddle DL, Blumenthal T, Meyer BJ, Priess JR, editors. Evolution 2nd edition. Cold Spring Harbor (NY): Cold Spring Harbor Laboratory Press; 1997 Chapter 29 (1997) PMID: 21413220
Fitch DHA, Kelley Thomas W

A bow-tie genetic architecture for morphogenesis suggested by a genome-wide RNAi screen in Caenorhabditis elegans.
PLoS Genet (2011 Mar) PMC3048373 free full-text archive
Nelson MD, Zhou E, Kiontke K, Fradin H, Maldonado G, Martin D, Shah K, Fitch DH

Phenotypic plasticity: different teeth for different feasts.
Curr Biol (2010 Sep 14) PMID: 20833313
Kiontke K, Fitch DH

Evolution of early embryogenesis in rhabditid nematodes.
Dev Biol (2009 Nov 01) PMC2763944 free full-text archive
Brauchle M, Kiontke K, MacMenamin P, Fitch DH, Piano F

Dropout alignment allows homology recognition and evolutionary analysis of rDNA intergenic spacers.
J Mol Evol (2008 Apr) PMID: 18363028
Ryu S, Do Y, Fitch DH, Kim W, Mishra B

Introduction to nematode evolution and ecology.
WormBook (2005 Aug 31) PMC4781023 free full-text archive
Fitch DH

The phylogenetic relationships of Caenorhabditis and other rhabditids.
WormBook (2005 Aug 11) PMC4781183 free full-text archive
Kiontke K, Fitch DH

Trends, stasis, and drift in the evolution of nematode vulva development.
Curr Biol (2007 Nov 20) PMID: 18024125
Kiontke K, Barriere A, Kolotuev I, Podbilewicz B, Sommer R, Fitch DH, Felix MA

Caenorhabditis evolution: if they all look alike, you aren't looking hard enough.
Trends Genet (2007 Mar) PMID: 17275130
Haag ES, Chamberlin H, Coghlan A, Fitch DH, Peters AD, Schulenburg H

Novel gain-of-function alleles demonstrate a role for the heterochronic gene lin-41 in C. elegans male tail tip morphogenesis.
Dev Biol (2006 Sep 01) PMID: 16806150
Del Rio-Albrechtsen T, Kiontke K, Chiou SY, Fitch DH

Evolution: an ecological context for C. elegans.
Curr Biol (2005 Sep 06) PMID: 16139194
Fitch DH

Autosomal genes of autosomal/X-linked duplicated gene pairs and germ-line proliferation in Caenorhabditis elegans.
Genetics (2005 Apr) PMC1449572 free full-text archive
Maciejowski J, Ahn JH, Cipriani PG, Killian DJ, Chaudhary AL, Lee JI, Voutev R, Johnsen RC, Baillie DL, Gunsalus KC, Fitch DH, Hubbard EJ

Initial Sequence and Protein Modeling Results of a Mitochondrial Genome Project on Understudied Invertebrate Phyla.
Biol Bull (2004 Oct) PMID: 27690613
Robbins GE, Giribet G, Kiontke K, Fitch DH, Boore JL, Campbell RK

Caenorhabditis phylogeny predicts convergence of hermaphroditism and extensive intron loss.
Proc Natl Acad Sci U S A (2004 Jun 15) PMC428462 free full-text archive
Kiontke K, Gavin NP, Raynes Y, Roehrig C, Piano F, Fitch DH

The genome sequence of Caenorhabditis briggsae: a platform for comparative genomics.
PLoS Biol (2003 Nov) PMC261899 free full-text archive
Stein LD, Bao Z, Blasiar D, Blumenthal T, Brent MR, Chen N, Chinwalla A, Clarke L, Clee C, Coghlan A, Coulson A, D'Eustachio P, Fitch DH, Fulton LA, Fulton RE, Griffiths-Jones S, Harris TW, Hillier LW, Kamath R, Kuwabara PE, Mardis ER, Marra MA, Miner TL, Minx P, Mullikin JC, Plumb RW, Rogers J, Schein JE, Sohrmann M, Spieth J, Stajich JE, Wei C, Willey D, Wilson RK, Durbin R, Waterston RH

Absence of wolbachia in nonfilariid nematodes.
J Nematol (2003 Sep) PMC2620650 free full-text archive
Bordenstein SR, Fitch DH, Werren JH

One small step for worms, one giant leap for "Bauplan"?
Evol Dev (2002 Jul-Aug) PMID: 12168615
Fitch DH, Sudhaus W

TLP-1 is an asymmetric cell fate determinant that responds to Wnt signals and controls male tail tip morphogenesis in C. elegans.
Development (2002 Mar) PMID: 11880358
Zhao X, Yang Y, Fitch DH, Herman MA

Evolution of "rhabditidae" and the male tail.
J Nematol (2000 Sep) PMC2620451 free full-text archive
Fitch DH

Morphogenesis of the Caenorhabditis elegans male tail tip.
Dev Biol (1999 Mar 01) PMID: 10049567
Nguyen CQ, Hall DH, Yang Y, Fitch DH

Evolution of male tail development in rhabditid nematodes related to Caenorhabditis elegans.
Syst Biol (1997 Mar) PMID: 11975351
Fitch DH

Variable cell positions and cell contacts underlie morphological evolution of the rays in the male tails of nematodes related to Caenorhabditis elegans.
Dev Biol (1995 Aug) PMID: 7649384
Fitch DH, Emmons SW

18S ribosomal RNA gene phylogeny for some Rhabditidae related to Caenorhabditis.
Mol Biol Evol (1995 Mar) PMID: 7700158
Fitch DH, Bugaj-Gaweda B, Emmons SW

Widespread occurrence of the Tc1 transposon family: Tc1-like transposons from teleost fish.
Mol Gen Genet (1994 Sep 28) PMID: 7969029
Radice AD, Bugaj B, Fitch DH, Emmons SW

Low codon bias and high rates of synonymous substitution in Drosophila hydei and D. melanogaster histone genes.
Mol Biol Evol (1993 Mar) PMID: 8487638
Fitch DH, Strausbaugh LD

Fetal recruitment of anthropoid gamma-globin genes. Findings from phylogenetic analyses involving the 5'-flanking sequences of the psi gamma 1 globin gene of spider monkey Ateles geoffroyi.
J Mol Biol (1992 Apr 05) PMID: 1569563
Hayasaka K, Fitch DH, Slightom JL, Goodman M

Pattern formation in the nematode epidermis: determination of the arrangement of peripheral sense organs in the C. elegans male tail.
Development (1991 Oct) PMID: 1782863
Baird SE, Fitch DH, Kassem IA, Emmons SW

Duplication of the gamma-globin gene mediated by L1 long interspersed repetitive elements in an early ancestor of simian primates.
Proc Natl Acad Sci U S A (1991 Aug 15) PMC52302 free full-text archive
Fitch DH, Bailey WJ, Tagle DA, Goodman M, Sieu L, Slightom JL

Phylogenetic scanning: a computer-assisted algorithm for mapping gene conversions and other recombinational events.
Comput Appl Biosci (1991 Apr) PMID: 2059846
Fitch DH, Goodman M

Molecular evolution of the psi eta-globin gene locus: gibbon phylogeny and the hominoid slowdown.
Mol Biol Evol (1991 Mar) PMID: 2046542
Bailey WJ, Fitch DH, Tagle DA, Czelusniak J, Slightom JL, Goodman M

On the origins of tandemly repeated genes: does histone gene copy number in Drosophila reflect chromosomal location?
Chromosoma (1990 Apr) PMID: 2113451
Fitch DH, Strausbaugh LD, Barrett V

Primate evolution at the DNA level and a classification of hominoids.
J Mol Evol (1990 Mar) PMID: 2109087
Goodman M, Tagle DA, Fitch DH, Bailey W, Czelusniak J, Koop BF, Benson P, Slightom JL

Molecular history of gene conversions in the primate fetal gamma-globin genes. Nucleotide sequences from the common gibbon, Hylobates lar.
J Biol Chem (1990 Jan 15) PMID: 2295619
Fitch DH, Mainone C, Goodman M, Slightom JL

Molecular phylogeny of the family of apes and humans.
Genome (1989) PMID: 2687100
Goodman M, Koop BF, Czelusniak J, Fitch DH, Tagle DA, Slightom JL

The spider monkey psi eta-globin gene and surrounding sequences: recent or ancient insertions of LINEs and SINEs?
Genomics (1988 Oct) PMID: 2852163
Fitch DH, Mainone C, Slightom JL, Goodman M