ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Chlamydomonas  (4)
  • 1980-1984  (4)
  • 1
    ISSN: 1432-0983
    Keywords: Chlamydomonas ; Chloroplast genes ; Segregation ; Recombination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Chloroplast mutations in the green alga Chlamydomonas reinhardtii exhibit a predominantly maternal pattern of inheritance and this pattern can be perturbed by UV irradiation of the maternal gametes prior to mating. In a series of crosses over a range of UV doses, the transmission, segregation, and recombination of mutations at three closely linked chloroplast loci have been examined by pedigree analysis of products arising from the first three post-zygotic divisions. Stocks used in these crosses were constructed to permit identification of the nuclear products of each of the two meiotic divisions and the first post-meiotic mitotic division. A bias toward maternal alleles at all three chloroplast loci was observed in all pedigrees and in zygote clones analyzed from the same crosses many generations after meiosis. This bias decreased with increasing UV dose and with each subsequent division. Segregation of chloroplast genes was rapid during the first three post-zygotic divisions. The type of segregation event from which a given heteroplasmic cell arose had a significant effect on its most likely segregation. pattern in the subsequent division. The results presented here have been discussed in terms of published models of chloroplast gene segregation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-0983
    Keywords: Chlamydomonas ; Chloroplast ; Organelle genetics ; Streptomycin dependence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In the green alga Chlamydomonas reinhardtii, reciprocal crosses between strains carrying non-allelic chloroplast mutations to streptomycin dependence (sd-u) produce streptomycin sensitive (sd-u +) recombinant progeny. Transfer of these sd-u +progeny to streptomycin-containing medium results in a much higher frequency of recovery of streptomycin dependent isolates than expected by mutation. Failure to recover the more commonly encountered class of streptomycin resistant mutants also suggests that mutation is not responsible for appearance of the new dependent isolates. Backcrosses of these new sd-u isolates to strains carrying the original sd-u mutations demonstrate their allelism with the sd-u mutation contributed by the mt +parent. Earlier work by Schimmer and Arnold (1969, 1970a-d) indicated that newly isolated sensitive revertants of the streptomycin dependent mutant sd-u-3-18 also yielded high frequencies of sd-u cells but these were never analyzed genetically. We have now obtained new sd-u. isolates from streptomycin sensitive revertants of sd-u-318 and shown them all to be allelic with the original sd-u3-18 mutation. Thus “hidden” sd-u alleles can coexist with sd-u +alleles in heteroplasmic cells. These heteroplasmic cells are streptomycin sensitive in phenotype and may arise in crosses or from new mutation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-0983
    Keywords: Chlamydomonas ; Non-photosynthetic mutations ; Ribosome biogenesis ; Chloroplast ribosomal proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The allelic nuclear mutations of Chlamydomonas reinhardtii, cr-6 and cr-7, result in the loss of two proteins from the large subunit of the chloroplast ribosome. One of these proteins, L-13, is synthesized in the chloroplast and the other, L29, is made in the cytoplasm. The loss of these two proteins is correlated with the inability of the large subunits of the chloroplast ribosomes to form monomers which incorporate labeled phenylalanine at normal rates in response to a polyuridylic acid template. Using antisera raised against L13 and L29, we found that protein L-13 was synthesized in appreciable amounts in pulse labeled cells of cr-6 and cr-7, but protein L-29 was not. We conclude that the inability to synthesize protein L29 is a primary defect in both cr-6 and cr-7 and that this protein is required for the stable assembly of protein L-13 into chloroplast ribosomes. The absence of one or both of these proteins from the large subunit of chloroplast ribosomes of the mutants interferes with the ability of the small and large subunits to associate properly into normal 70S monomers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-5028
    Keywords: ATPase ; Chlamydomonas ; chloroplast ; complementation ; recombination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have carried out a molecular and genetic analysis of the chloroplast ATPase in Chlamydomonas reinhardtii. Recombination and complementation studies on 16 independently isolated chloroplast mutations affecting this complex demonstrated that they represent alleles in five distinct chloroplast genes. One of these five, the ac-u-c locus, has been positioned on the physical map of the chloroplast DNA by deletion mutations. The use of cloned spinach chloroplast ATPase genes in heterologous hybridizations to Chlamydomonas chloroplast DNA has allowed us to localize three or possibly four of the ATPase genes on the physical map. The beta and probably the epsilon subunit genes of Chlamydomonas CF1 lie within the same region of chloroplast DNA as the ac-u-c locus, while the alpha and proteolipid subunit genes appear to map adjacent to one another approximately 20 kbp away. Unlike the arrangement in higher plants, these two pairs of genes are separated from each other by an inverted repeat.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...