Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 1432-2048
    Keywords: Key words: Rachis elongation ; Ethylene ; Expansin ; Marsilea ; Regnellidium ; Submergence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract. To investigate the evolutionary history of expansins and their role in cell elongation in early land plants, we isolated two α-expansin genes, Mq-EXP1 and Rd-EXP1, respectively, from the semiaquatic ferns Marsilea quadrifolia L. and Regnellidium diphyllum Lindm. The deduced amino acid sequences of the fern expansins exhibit a high degree of identity to those of seed plants, showing that expansin genes were conserved during the evolution of vascular plants. Gel-blot analysis of M. quadrifolia and R. diphyllum genomic DNA indicated that, in both ferns, α-expansins are encoded by multigene families. Expression of α-expansin genes probed with Mq-EXP1 was confined to the elongating region of the Marsilea rachis. Cell-wall proteins of M.␣quadrifolia induced in-vitro extension of acidified cucumber cell walls. In R. diphyllum, expression of Rd-EXP1 increased when elongation of the rachis was enhanced by submergence or ethylene. These results indicate that α-expansins act as wall-loosening proteins in ferns, as has been proposed for angiosperms. In addition, Rd-EXP1 may play a role in mediating elongation of the rachis in submerged plants.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1435-232X
    Keywords: Key words Bone mineral density ; FokI ; DNA polymorphism ; Vitamin D receptor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We undertook this study in order to examine the association between bone mineral density (BMD) and a polymorphism at the first of two potential translation initiation codons in the vitamin D receptor (VDR) gene. This polymorphism was detected by restriction fragment length polymorphism analysis, using polymerase chain reaction (PCR) and the restriction endonuclease FokI. The f allele indicates the presence of the FokI site, and the F allele its absence. The FokI genotype was determined in 174 postmenopausal Korean women, aged 43–71 years. The distribution of FokI genotypes in Koreans was found not to differ significantly from those found in Caucasians and Japanese, although it does differ significantly from that found in the black American population. We observed a significant association between the FokI polymorphism and lumbar BMD; P = 0.048, analysis of covariance [ANCOVA], but no association with femoral neck BMD (P = 0.505, ANCOVA). Those with the ff genotype had a 13.3% lower BMD in the lumbar spine than the FF subjects. In addition, a significantly higher prevalence of the ff genotype was observed in osteoporotic compared with osteopenic or normal women (P = 0.036, χ2 test). These data suggest that the ff genotype of the VDR gene correlates with decreased BMD in the lumbar spine in postmenopausal Korean women.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...