\4 integrin expression onin vitro andin vivo metastatic variants of lewis lung carcinoma

The expression of 4, 6, and 1 integrin subunits has been investigated on somein vitro andin vivo murine metastatic variants derived from Lewis lung carcinoma (3LL). By the use of monoclonal antibodies which recognizes different epitopes of 6, 1, and 4 subunits we demonstrate that 6 and 1 subunits are expressed in all metastatic variants of 3LL irrespective of their metastatic potential, whereas 4 subunit is expressed only in highly metastasizing cells of 3LL. Northern blots of different metastatic variants probed with 1 and 4 subunits demonstrate thata) significant amounts of 1 mRNA were detected in all metastatic variants of 3LL;b) mRNA corresponding to the described entire coding sequence of 4 subunit is expressed only on highly metastasizing cells of 3LL. We conclude that 4 subunit is specifically expressed in highly metastasizig cells of 3LL while is undetectable in lower metastasizing ones.     

Identification of ‘Amigo’ and ‘Kavkaz’ translocations in Ohio soft red winter wheats (Triticum aestivum L.)

One cultivar (GR876) and two advanced Ohio soft red winter wheat lines (OH413 and OH414), with Kavkaz in their pedigrees, were examined for the presence of the Kavkaz, 1RS/1BL rye/wheat chromosome translocation. Another advanced line (OH416), with Amigo in its pedigree, was examined for the presence of the Amigo, 1RS/1AL translocation. Only two satellited chromosomes were observed in most mitotic root-tip cells from GR876, OH413, and OH414, compared to four in most cells from OH416. Heteromorphic bivalents were observed in most PMCs from hybrids produced by crossing GR876, OH413, and OH414 as females to Chinese Spring. No heteromorphic bivalents were observed in PMCs from OH416 x Chinese Spring hybrids. When GR876 and the Ohio lines were hybridized with Chinese Spring dimonotelosomic-1B, telosomic trivalents, consisting of the short- and longarm telosomes paired with chromosome 1B, were only observed in PMCs from 43-chromosome hybrids involving OH416. The long-arm telosome paired with the translocation chromosome, while the short-arm telosome remained unpaired in all other 43-chromosome hybrids. Separation of gliadin proteins from GR876 and the Ohio lines by PAGE revealed that secalin bands for GR876, OH413, and OH414, migrated similarly to the secalins for Kavkaz. Bands for OH416, identified as possible secalins, migrated similarly to those for Amigo. Cultivar GR876 and advanced Ohio soft red winter wheat lines OH413 and OH414 carry the Kavkaz translocation, while OH416 carries the Amigo translocation.Communicated by K. Tsunewaki     

A pistil-specific thaumatin/PR5-like protein gene of Japanese pear (Pyrus serotina): sequence and promoter activity of the 5′ region in transgenic tobacco

The genomic clone encoding the pistil-specific thaumatin/PR5-like protein (PsTL1) was isolated from Japanese pear (Pyrus serotina). Sequence analysis showed that the genomic clone contained the 5-flanking sequence of 2.4 kb, the 3-flanking sequence of 648 bp and the coding region interrupted by a intron of 351 bp. A sequence motif conserved in some pistil self-incompatibility gene promoters of solanaceous and brassicaceous species was located in the 5-flanking region of the PsTL1 gene. The 2.4 kb 5-flanking region was fused to the GUS coding sequence and transferred to tobacco. Transgenic tobacco showed GUS activity in pistil and, at low level, in anther, but not in other floral organs and leaf. Histochemical analysis localized GUS activity to stigma, transmitting tissue, anther and pollen of transgenic tobacco.     

Field performance of derived generations of transgenic tobacco

Two inbred cultivars of Nicotiana tabacum (tobacco), Samsun and Xanthi, were transformed with the plasmid pBI 121 using Bin 19 in Agrobacterium tumefaciens. The plasmid carries the nptII gene conferring kanamycin resistance and the uidA gene encoding -glucuronidase (GUS). Progeny carrying the genes in the homozygous condition were identified and selfed over several generations. One line homozygous for the introduced genes and one untransformed control from each cultivar were then selected and crossed reciprocally to give four families per cultivar. Seeds from each family were grown in a replicated field trial and all plants scored for a range of morphological and agronomic characters. In addition, leaf samples were taken and GUS activity measured. In the Samsun material, which contained one copy of the introduced gene at a single locus and showed high levels of GUS expression, the transformed homozygote showed twice the level of GUS activity as the hemizygotes, wheareas in the Xanthi line, which had a lower level of GUS, the hemizygotes showed the same level of GUS activity as the transformed homozygote. The agronomic data showed differences between the families, but the source of such differences could not be ascribed unambiguously. The results are discussed in the light of related information on gene expression and field performance from other transgenic material.     

Direct Organogenesis from Mature Leaf and Petiole Explants of Eryngium Foetidum L.

Eryngium foetidum L. plants were regenerated from mature leaf and petiole explants through direct organogenesis without intervening callus phase. From leaf explants, adventitious multiple shoots raised on Murashige and Skoog (MS) medium supplemented with 4.43 M benzylaminopurine (BAP) and 0.57 M indole-3-acetic acid (IAA), whereas in petiole explants shoot regeneration occurred at 8.86 M BAP and 0.57 M IAAA. 80% of the leaf explants and 44% of petiole explants produced shoots after four weeks of culture. The regenerated plants were rooted on MS medium supplemented with 2.46 M indole-3-butyric acid and 2.88 M gibberellic acid. The plants were successfully established in the soil and showed 70.9% survival in the field.     

Evidence for non-proteinaceous inhibitor(s) of β-glucuronidase in wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis>L.) leaf and root tissues

The GUS gene of E. coli, encoding -glucuronidase, has been widely used as a reporter gene in plant transformation. However, -glucuronidase activity in transgenic wheat leaf or root tissue is rarely observed or reported. To address this question, we investigated three wheat lines transformed with the GUS reporter gene. We found all three lines expressed GUS mRNA as well as -glucuronidase protein in their leaf and root tissues as detected by RNA gel blot, ELISA, and immunoblot analyses. However, -glucuronidase enzyme activity was only detected in pollen grains from the transgenic plants. Fluorometric and histochemical assays performed in the presence of wheat tissue extracts indicated that wheat leaf and root tissues contain inhibitor(s) of -glucuronidase activity, but pollen grains contain much lower concentrations. Further characterizations indicated that the inhibitor(s) is of low molecular weight (<10 kDa) and is non-proteinaceous.     

Genetic analysis of two wheat cultivars, ‘Sonalika’ and ‘WL 711’ for reaction to leaf rust (Puccinia recondita)

Summary Genetic analysis for leaf rust reaction of two widely adapted cultivars, Sonalika and WL 711, has been done using 21 near isogenic Lr lines and rust culture IL004 — avirulent on the two cultivars and all the Lr lines used. The segregation pattern in the F₂ generation indicated the presence of a recessive gene in Sonalika and of a dominant gene in WL 711. These genes in cultivars Sonalika and WL 711 have been identified as Lr 11 and Lr 13, respectively. Gene Lr 13 is no longer effective in WL 711 but it continues to give field resistance in the backgrounds of Chris, Prelude and Thatcher. There has been no significant change in the virulence spectrum of the leaf rust pathogen in India with the release of WL 711. High susceptibility of WL 711 seems to be due to the evolution of more aggressive forms of the pathogen to this cultivar. The gene Lr 11, which behaves as a recessive in Sonalika, was effective against leaf rust when this cultivar was released. The high susceptibility of Sonalika is probably due to an increase in the frequency of race 77 virulent on Lr 11. Lr 11 has shown a dominance reversal in the background of Sonalika. Present results suggest that interaction of resistance genes with the background genotype must be studied for their effective use in breeding programme.