Open AccessLeishmania majorFriedlin chromosome 1 has an unusual distribution of protein-coding genes
Author(s) -
Peter J. Myler,
Lindsey Audleman,
Theo deVos,
Greg T. Hixson,
Patti Kiser,
Craig A. Lemley,
Charles L. Magness,
Erika Rickel,
Ellen C. Sisk,
Susan M. Sunkin,
Steven Swartzell,
Thomas Westlake,
Patrick Bastien,
Guoliang Fu,
Alasdair Ivens,
Kenneth Stuart
Publication year - 1999
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.96.6.2902
Subject(s) - biology , gene , genetics , genome , chromosome , dna , subtelomere , coding region , repeated sequence , dna sequencing
Leishmania are evolutionarily ancient protozoans (Kinetoplastidae) and important human pathogens that cause a spectrum of diseases ranging from the asymptomatic to the lethal. TheLeishmania genome is relatively small [≈34 megabases (Mb)], lacks substantial repetitive DNA, and is distributed among 36 chromosomes pairs ranging in size from 0.3 Mb to 2.5 Mb, making it a useful candidate for complete genome sequence determination. We report here the nucleotide sequence of the smallest chromosome, chr1. The sequence of chr1 has a 257-kilobase region that is densely packed with 79 protein-coding genes. This region is flanked by telomeric and subtelomeric repetitive elements that vary in number and content among the chr1 homologs, resulting in an ≈27.5-kilobase size difference. Strikingly, the first 29 genes are all encoded on one DNA strand, whereas the remaining 50 genes are encoded on the opposite strand. Based on the gene density of chr1, we predict a total of ≈9,800 genes inLeishmania , of which 40% may encode unknown proteins.