Abstract
Coccidioides immitis, cause of a recent epidemic of "Valley fever" in California, is typical of many eukaryotic microbes in that mating and meiosis have yet to be reported, but it is not clear whether sex is truly absent or just cryptic. To find out, we have undertaken a population genetic study using PCR amplification, screening for single-strand conformation polymorphisms, and direct DNA sequencing to find molecular markers with nucleotide-level resolution. Both population genetic and phylogenetic analyses indicate that C. immitis is almost completely recombining. To our knowledge, this study is the first to find molecular evidence for recombination in a fungus for which no sexual stage has yet been described. These results motivate a directed search for mating and meiosis and illustrate the utility of single-strand conformation polymorphism and sequencing with arbitrary primer pairs in molecular population genetics.
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- Altschul S. F., Gish W., Miller W., Myers E. W., Lipman D. J. Basic local alignment search tool. J Mol Biol. 1990 Oct 5;215(3):403–410. doi: 10.1016/S0022-2836(05)80360-2. [DOI] [PubMed] [Google Scholar]
- Brown A. H., Feldman M. W., Nevo E. Multilocus Structure of Natural Populations of HORDEUM SPONTANEUM. Genetics. 1980 Oct;96(2):523–536. doi: 10.1093/genetics/96.2.523. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Burt A., Carter D. A., White T. J., Taylor J. W. DNA sequencing with arbitrary primer pairs. Mol Ecol. 1994 Oct;3(5):523–525. doi: 10.1111/j.1365-294x.1994.tb00131.x. [DOI] [PubMed] [Google Scholar]
- Clark A. G., Lanigan C. M. Prospects for estimating nucleotide divergence with RAPDs. Mol Biol Evol. 1993 Sep;10(5):1096–1111. doi: 10.1093/oxfordjournals.molbev.a040057. [DOI] [PubMed] [Google Scholar]
- DuBose R. F., Dykhuizen D. E., Hartl D. L. Genetic exchange among natural isolates of bacteria: recombination within the phoA gene of Escherichia coli. Proc Natl Acad Sci U S A. 1988 Sep;85(18):7036–7040. doi: 10.1073/pnas.85.18.7036. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dykhuizen D. E., Green L. Recombination in Escherichia coli and the definition of biological species. J Bacteriol. 1991 Nov;173(22):7257–7268. doi: 10.1128/jb.173.22.7257-7268.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ellsworth D. L., Rittenhouse K. D., Honeycutt R. L. Artifactual variation in randomly amplified polymorphic DNA banding patterns. Biotechniques. 1993 Feb;14(2):214–217. [PubMed] [Google Scholar]
- Gish W., States D. J. Identification of protein coding regions by database similarity search. Nat Genet. 1993 Mar;3(3):266–272. doi: 10.1038/ng0393-266. [DOI] [PubMed] [Google Scholar]
- Kishino H., Hasegawa M. Evaluation of the maximum likelihood estimate of the evolutionary tree topologies from DNA sequence data, and the branching order in hominoidea. J Mol Evol. 1989 Aug;29(2):170–179. doi: 10.1007/BF02100115. [DOI] [PubMed] [Google Scholar]
- Orita M., Iwahana H., Kanazawa H., Hayashi K., Sekiya T. Detection of polymorphisms of human DNA by gel electrophoresis as single-strand conformation polymorphisms. Proc Natl Acad Sci U S A. 1989 Apr;86(8):2766–2770. doi: 10.1073/pnas.86.8.2766. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pan S., Sigler L., Cole G. T. Evidence for a phylogenetic connection between Coccidioides immitis and Uncinocarpus reesii (Onygenaceae). Microbiology. 1994 Jun;140(Pt 6):1481–1494. doi: 10.1099/00221287-140-6-1481. [DOI] [PubMed] [Google Scholar]
- Pappagianis D. Epidemiology of coccidioidomycosis. Curr Top Med Mycol. 1988;2:199–238. doi: 10.1007/978-1-4612-3730-3_6. [DOI] [PubMed] [Google Scholar]
- Pappagianis D. Marked increase in cases of coccidioidomycosis in California: 1991, 1992, and 1993. Clin Infect Dis. 1994 Aug;19 (Suppl 1):S14–S18. doi: 10.1093/clinids/19.supplement_1.14. [DOI] [PubMed] [Google Scholar]
- Riedy M. F., Hamilton W. J., 3rd, Aquadro C. F. Excess of non-parental bands in offspring from known primate pedigrees assayed using RAPD PCR. Nucleic Acids Res. 1992 Feb 25;20(4):918–918. doi: 10.1093/nar/20.4.918. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith J. M., Smith N. H., O'Rourke M., Spratt B. G. How clonal are bacteria? Proc Natl Acad Sci U S A. 1993 May 15;90(10):4384–4388. doi: 10.1073/pnas.90.10.4384. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tibayrenc M., Kjellberg F., Arnaud J., Oury B., Brenière S. F., Dardé M. L., Ayala F. J. Are eukaryotic microorganisms clonal or sexual? A population genetics vantage. Proc Natl Acad Sci U S A. 1991 Jun 15;88(12):5129–5133. doi: 10.1073/pnas.88.12.5129. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tibayrenc M., Kjellberg F., Ayala F. J. A clonal theory of parasitic protozoa: the population structures of Entamoeba, Giardia, Leishmania, Naegleria, Plasmodium, Trichomonas, and Trypanosoma and their medical and taxonomical consequences. Proc Natl Acad Sci U S A. 1990 Apr;87(7):2414–2418. doi: 10.1073/pnas.87.7.2414. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tibayrenc M., Neubauer K., Barnabé C., Guerrini F., Skarecky D., Ayala F. J. Genetic characterization of six parasitic protozoa: parity between random-primer DNA typing and multilocus enzyme electrophoresis. Proc Natl Acad Sci U S A. 1993 Feb 15;90(4):1335–1339. doi: 10.1073/pnas.90.4.1335. [DOI] [PMC free article] [PubMed] [Google Scholar]