Interspecific hybridization is a useful technique to introduce characteristics from wild species into crops. Garden asparagus (
Asparagus officinalis
, 2
n
= 2
x
= 20) is an economically important ...vegetable that is native to the Mediterranean region but widely cultivated in many countries. The genus
Asparagus
is comprised of over 100 species.
Asparagus kiusianus
(2
n
= 2
x
= 20) is a wild asparagus species endemic to Japan. This species occurs on the coast and is likely to be a salt-resistant species. Although the geographic distribution of these two species is not close, molecular phylogenetic analysis demonstrated that these two species are closely related. In this study, a reciprocal cross between
A. officinalis
and
A. kiusianus
was carried out by hand pollination, and progeny were obtained from both crossings. These progeny exhibited a morphologically intermediate phenotype in terms of flower shape, and restriction fragment length polymorphism analysis confirmed that these were indeed interspecific hybrids. The interspecific hybrids were fertile, and backcross progeny with garden asparagus was also generated. These interspecific hybrids are expected to supply novel traits to garden asparagus.
Garden asparagus (Asparagus officinalis L.) has homochlamydeous flowers. Like Liliaceae plants such as lily and tulip, the perianths of asparagus have two whorls of almost identical petaloid organs, ...called tepals. Floral structures of these homochlamydeous flowers could be explained by a modified ABC model, in which the expression of the class B genes has expanded to whorl 1, so that the organs of whorls 1 and 2 have the same petaloid structure. In this study, we isolated and characterized two GLOBOSA-like genes (AOGLOA and AOGLOB), one of class B gene, from asparagus. Southern blot showed that AOGLOA and AOGLOB genes are single copy genes. Northern blot analysis indicated that these genes were specifically expressed in male and female flowers. In situ hybridization showed that the expression of AOGLOA and AOGLOB genes is confined to whorls 2 and 3 (inner tepal and stamen) and not detected in whorl 1 (outer tepal). The other asparagus class B gene, AODEF, was also not expressed in outer tepal Park et al. (2003) Plant Mol Biol. 51: 867. These results indicate that the class B genes are not involved in the outer tepal development in asparagus, not supporting the modified ABC model in asparagus.
Alstroemeria (Liliales) has two layers of petaloid tepals, in which the often spotted narrow inner tepals can be distinguished easily from the wider outer tepals. In order to explore this floral ...morphology in Alstroemeria, we investigated the tepal morphology and the expression patterns of three class B genes, whose homologs in eudicots have been shown previously to be involved in petal and stamen development. The two DEF-like genes (AlsDEFa and AlsDEFb) and the one GLO-like gene (AlsGLO) of Alstroemeria ligtu were isolated by rapid amplification of cDNA ends (RACE). Northern hybridization, reverse transcription-PCR (RT-PCR) and in situ hybridization analyses indicated that AlsDEFb and AlsGLO were expressed in whorls 1, 2 and 3 (outer tepals, inner tepals and stamens, respectively), whereas AlsDEFa expression was detected only in whorls 2 and 3. These results suggest that in A. ligtu, AlsDEFb and AlsGLO would participate in determining the organ identity of the two-layered petaloid tepals and stamens, which is in support of the modified ABC model. Additionally, the distinctive expression patterns of AlsDEFa and AlsDEFb might be related to morphological differences between the two-layered tepals.
•PARP plays a critical role in liver ischemia/reperfusion-induced injury.•PARP is more critical than caspases in post-hypoxic cell injury.•PARP and caspases induce post-hypoxic cell death, ...independent of each other.•Hypoxia-induced PARP activation is redox-dependent, more than caspases.•PARP induces necrotic programmed cell death, parthanatos and necroptosis.
Poly(ADP-ribose) polymerase (PARP) is a DNA-repairing enzyme activated by extreme genomic stress, and therefore is potently activated in the remnant liver suffering from ischemia after surgical resection. However, the impact of PARP on post-ischemic liver injury has not been elucidated yet.
We investigated the impact of PARP on murine hepatocyte/liver injury induced by hypoxia/ischemia, respectively.
PJ34, a specific inhibitor of PARP, markedly protected against hypoxia/reoxygenation (H/R)-induced cell death, though z-VAD-fmk, a pan-caspase inhibitor similarly showed the protective effect. PJ34 did not affect H/R-induced caspase activity or caspase-mediated cell death. z-VAD-fmk also did not affect the production of PAR (i.e., PARP activity). Therefore, PARP- and caspase-mediated cell death occurred in a mechanism independent of each other in H/R. H/R immediately induced activation of PARP and cell death afterwards, both of which were suppressed by PJ34 or Trolox, an antioxidant. This suggests that H/R-induced cell death occurred redox-dependently through PARP activation. H/R and OS induced nuclear translocation of apoptosis inducing factor (AIF, a marker of parthanatos) and RIP1-RIP3 interaction (a marker of necroptosis), both of which were suppressed by PJ34. H/R induced PARP-mediated parthanatos and necroptosis redox-dependently. In mouse experiments, PJ34 significantly reduced serum levels of AST, ALT & LDH and areas of hepatic necrosis after liver ischemia/reperfusion, similar to z-VAD-fmk or Trolox.
PARP, activated by ischemic damage and/or oxidative stress, may play a critical role in post-ischemic liver injury by inducing programmed necrosis (parthanatos and necroptosis). PARP inhibition may be one of the promising strategies against post-ischemic liver injury.
Asparagus (Asparagaceae) is a large genus that is widely distributed in arid and subarid regions of the Old World. To investigate the phylogenetic relationships within this genus, the intron of petB ...and the intergenic region between petD and rpoA of chloroplast DNA (cpDNA) were sequenced. A strict consensus tree resulting from the phylogenetic analysis indicates that southern African species comprise a potentially paraphyletic assemblage and that Eurasian species are monophyletic. This result suggests that the genus Asparagus originated in southern Africa, and that Eurasian species originated from a southern African progenitor. Moreover, extensive survey of the intergenic region between trnL and trnF and the intron of trnL of cpDNA in species of the genus Asparagus displayed no sequence differences despite the non‐coding regions frequently used to reconstruct intrageneric phylogenies. Therefore, we hypothesized that rapid radiation of this genus might have been influenced by the gaining of unique characteristics, such as phylloclades, in order to adapt to the dry environment.
Orchids are commercially important plants with flowers that are unique and very specialized in shape and color. The flowers consist mostly of sepals, lateral petals, lip (labellum) and column, and ...are zygomorphic and resupinate. Whereas most orchid species have petaloid tepals in the first and second whorls,
Habenaria radiata has a flower with greenish sepals and white lateral petals and lip. ‘Hishou’, one of the cultivars of
H. radiata, is a floral homeotic mutant and has a petaloid median sepal and lip-like lateral sepals in the first whorl. Additionally, this cultivar often has non-resupinate flowers whereas wild-type
H. radiata flowers are resupinate. In the present study, we investigated the genetic inheritance of these characters in the ‘Hishou’ cultivar by crossing it with wild-type plants. Some intraspecific hybrids, which were confirmed by PCR-RFLP analysis, had flowers with a petaloid median sepal and lip-like lateral sepals in the first whorl, indicating that these were dominant characters. Since the remainder of the intraspecific hybrids had wild-type flowers, these characters must be heterozygous in ‘Hishou’ plants. Although ‘Hishou’ plants had non-resupinate flowers, intraspecific hybrid flowers were resupinate, even though they had the petaloid median sepal and lip-like lateral sepals. This result indicates that non-resupination must be a recessive character. Since sepal-petalization and triple lip characters of ‘Hishou’ inherited dominantly, these characters can be utilized for the breeding of
Habenaria species by intra- and interspecific crosses.
The AGAMOUS (AG) family of MADS-box genes plays important roles in controlling the development of the reproductive organs of flowering plants. To understand the molecular mechanisms behind the floral ...development in the orchid, we isolated and characterized two AG-like genes from Phalaenopsis that we denoted PhalAG1 and PhalAG2. Phylogenetic analysis indicated that PhalAG1 and PhalAG2 fall into different phylogenetic positions in the AG gene family as they belong to the C- and D-lineages, respectively. Reverse transcription-polymerase chair reaction (RT-PCR) analyses showed that PhalAG1 and PhalAG2 transcripts were detected in flower buds but not in vegetative organs. Moreover, in situ hybridization experiments revealed that PhalAG1 and PhalAG2 hybridization signals were observed in the lip, column, and ovule during the floral development of Phalaenopsis, with little difference between the expression patterns of the two genes. These results suggest that both AG-like genes in Phalaenopsis act redundantly with each other in floral development.
A late embryogenesis abundant (LEA) protein gene, ME-leaN4, from rape (Brassica napus) was successfully introduced into lettuce (Lactuca sativa L.) using Agrobacterium tumefaciens-mediated ...transformation. Infection by Agrobacterium strain EHA101 containing the binary vector pIG121-LEA was applied. Six independent transgenic lettuce plants were generated as a result. Transgenic lettuce demonstrated enhanced growth ability as compared to non-transformed control plants under salt-stress and water-deficit stress conditions. After 10-day growth under 100 mM NaCl condition in the hydroponics, average plant length and fresh weight of transgenic lettuce were 2.8 cm and 2.5 g plant-1, while control plants were only 0.2 cm and 0.3 g plant-1, respectively. The increased tolerance was also reflected by delayed wilting of leaves caused by water-deficit stress. These results suggest that growth characteristics were improved in transgenic lettuce plants constitutively expressing the rape LEA gene in response to salt- and water-deficit stress.
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