Molecular and General Genetics MGG

, Volume 246, Issue 1, pp 29–36 | Cite as

Molecular organization of Chlorella vulgaris chromosome I: presence of telomeric repeats that are conserved in higher plants

  • Takanobu Higashiyama
  • Sinya Maki
  • Takashi Yamada
Original Paper


The unicellular green alga Chlorella vulgaris (strain C-169) has a small genome (38.8 Mb) consisting of 16 chromosomes, which can be easily separated by CHEF gel electrophoresis. We have isolated and characterized the smallest chromosome (chromosome 1, 980 kb) to elucidate the fundamental molecular organization of a plant-type chromosome. Restriction mapping and sequence analyses revealed that the telomeres of this chromosome consist of 5′-TTTAGGG repeats running from the centromere towards the termini; this sequence is identical to those reported for several higher plants. This sequence is reiterated approximately 70 times at both termini, although individual clones exhibited microheterogeneity in both sequence and copy number of the repeats. Subtelomeric sequences proximal to the termini were totally different from each other: on the left arm, unique sequence elements (14–20 bp) which were specific to chromosome I, form a repeat array of 1.7 kb, whereas a 1.0 kb sequence on the right arm contained a poly(A)-associated element immediately next to the telomeric repeats. This element is repeated several times on chromosome I and many times on all the other chromosomes of this organism.

Key words

Chlorella vulgaris Small-sized chromosomes Pulsed field gel electrophoresis Physical mapping Telomeric repeats 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Aimi T, Yamada T, Murooka Y (1993) A group-I self-splicing intron in the nuclear small subunit rRNA-encoding gene of the green alga, Chlorella ellipsoidea C-87. Gene 134:65–71Google Scholar
  2. Berg DE, Howe MW (1989) Mobile DNA, American Society for Microbiology, Washington DCGoogle Scholar
  3. Blackburn EH (1991) Structure and function of telomeres. Nature 350:569–573Google Scholar
  4. Blackburn EH (1992) Telomerases. Annu Rev Biochem 61:13–129Google Scholar
  5. Boeke JD, Corces VG (1989) Transcription and reverse transcription of retrotransposons. Annu Rev Microbiol 43:403–434Google Scholar
  6. Broun P, Ganal MW, Tanksley SD (1992) Telomeric arrays display high levels of heritable polymorphism among closely related plant varieties. Proc Natl Acad Sci USA 89:1354–1357Google Scholar
  7. Chan CSM, Tye B-K (1980) Autonomously replicating sequences in Saccharomyces cerevisiae. Proc Natl Acad Sci USA 77:6329–6333Google Scholar
  8. Clarke L, Carbon J (1980) Isolation of a yeast centromere and construction of functional small circular chromosomes. Nature 305:504–509Google Scholar
  9. Deininger PL (1989) SINEs: short interspersed DNA elements in higher eucaryotes. In: Berg DE, Howe MM (ed) Mobile DNA. American Society for Microbiology, Washington DC, pp 619–636Google Scholar
  10. Fott B, Novakova M (1969) A monograph of the genus Chlorella. The freshwater species. In: Fott B (ed) Studies in phycology. Verlag Akademische Wissenschaft, Prague, pp 10–74Google Scholar
  11. Ganal MW, Lapitan NLV, Tanksley SD (1991) Macrostructure of tomato telomeres. Plant Cell 3:87–94Google Scholar
  12. Geiduschek EP (1988) Transcription by RNA polymerase III. Annu Rev Biochem 57:873–914Google Scholar
  13. Gilson E, Laroche T, Gasser SM (1993) Telomers and the functional architecture of the nucleus. Trends Cell Biol 3:128–134Google Scholar
  14. Govindjee, Braun BZ (1974) Light absorption, emission and photosynthesis. In: Stewart WDP (ed) Algal physiology and biochemistry. University of California Press, Berkeley - Los Angeles, pp 346–390Google Scholar
  15. Higashiyama T, Yamada T (1991) Electrophoretic karyotyping and chromosomal gene mapping of Chlorella. Nucleic Acids Res 19:6191–6195Google Scholar
  16. Lustig AJ, Kurtz S, Shore D (1990) Involvement of the silencer and UAS binding protein RAP1 in regulation of tlomere length. Science 250:549–553Google Scholar
  17. Maluszynska J, Heslop-Harrison JS (1991) Localization of tandemly repeated DNA sequences in Arabidopsis thaliana. Plant J 1:159–166Google Scholar
  18. McEachern MJ, Hicks JB (1993) Unusually large telomeric repeats in the yeast Candida albicans. Mol Cell Biol 13:551–560Google Scholar
  19. Murray AW, Szostak JW (1983) Construction of artificial chromosomes in yeast. Nature 305:189–193Google Scholar
  20. Newlon C (1988) Yeast chromosome replication and segregation. Microbiol Rev 52:568–601Google Scholar
  21. Petracek ME, Lefebvre PA, Silflow CD, Berman J (1990) Chlamydomonas telomere sequences are A+T-rich but contain three consecutive G:C base pairs. Proc Natl Acad Sci USA 87:8222–8226Google Scholar
  22. Richards EJ, Ausubel FM (1988) Isolation of a higher eukaryotic telomere from Arabidopsis thaliana. Cell 53:127–136Google Scholar
  23. Richards EJ, Goodman HM, Ausubel FM (1991) The centromere region of Arabidopsis thaliana chromosome I contains telomere-similar sequences. Nucleic Acids Res 19:3351–3357Google Scholar
  24. Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual (2nd edn). Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New YorkGoogle Scholar
  25. Szostak JW, Blackburn EH (1982) Cloning yeast telomeres on linear plasmid vectors. Cell 29:245–255Google Scholar
  26. Weiner AM, Dinninger PL, Efstratiadis A (1986) Nonviral retro transposons: genes, pseudogenes, and transposable elements generated by the reverse flow of genetic information. Annu Rev Biochem 55:631–661Google Scholar
  27. Yamada T (1982) Isolation and characterization of chloroplast DNA from Chlorella ellipsoidea. Plant Physiol 70:92–96Google Scholar
  28. Yamada T (1993) Cyanobacteria and algae. In: Murooka Y, Imanaka T (ed) Recombinant microbes for industrial and agricultural applications. Marcel Dekker, New York pp 701–712Google Scholar
  29. Yamada T, Maki S, Higashiyama T (1993) Nucleotide sequence of a Chlorella vulgaris α-tubulin gene. Plant Physiol 103:1467–1467Google Scholar
  30. Zakian VA (1989) Structure and function of telomeres. Annu Rev Genet 23:579–604Google Scholar

Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • Takanobu Higashiyama
    • 1
  • Sinya Maki
    • 1
  • Takashi Yamada
    • 1
  1. 1.Department of Fermentation TechnologyFaculty of Engineering, Hiroshima UniversityHigashi-Hiroshima 724Japan

Personalised recommendations