| RT-PCR |
Nodule formation |
up-regulated |
N/A |
enod40 is not an inducer of cell division per se, but other factors likely present only in the inner cortex are required to complete cell cycle activation. Stable constitutive expression of enod40 in transgenic plants resulted in a large proportion of dividing root cortical cells when grown under nitrogen-limited conditions Translation was observed in epidermal and outer cortical cells of intact roots. As well as accelerated nodulation. Further suggesting that our transient assay is related to the biological activity of enod40 in the root ortex. enod40 action in alfalfa roots. enod40 regulation in nodule organogenesis. (Sousa et al., 2001) Enod40 is a key regulatory gene expressed early during nodule organogenesis. Enod40 is one of the first molecular markers expressed at the onset of nodule organogenesis in the root pericycle and cortex. Enod40 has been proposed as one of the key regulatory genes involved in a signal transduction pathway activated during nodule initiation. (Jiménez-Zurdo et al., 2000) MsENOD40 transcripts can be detected within 24h after Rhizobium meliloti infection and are found not only in the root pericycle cells and nodule primordia as reported for both soybean and pea ENOD40, but also in cells typically classed as meristems: the distal ends of nodules and developing lateral roots, the margins of young leaf primordia, and the procambial cells of the stem and root.In 10-day-old nodules, MsENOD40 transcripts were restricted to the nodule meristem and to cells surrounding the vascular bundle (not shown). In mature (21-day or older) nodules, MsENOD40 transcripts were localized to the cells of the meristem and immediately adjacent to it, with the intensity of label decreasing in the invasion zone and older parts of the nodule. (Asad et al., 1994) Early nodulin genes are characteristically expressed during nodule morphogenesis. MsENOD40 would be expressed in mycorrhizal roots. because transcripts for these genes accumulate in the bacteria-free nodules elicited by R.Meliloti exopolysaccharide (exo) mutants or in alfalfa roots treated with auxin transport inhibitors. MsENOD40 transcripts accumulated in the cells of the pericycle and to a more limited extent in the epidermis and inner cortical cells, especially those containing immature arbuscules. Forming arbuscular mycorrhizae and Rhizobium-induced nodules.we show that mycorrhizae resemble nodules at the molecular level in that these two early nodulin genes are expressed. We also show that cytokinin induces both MsENOD2 and MsENOD40 expression in uninoculated roots,indicating this plant hormone may be part of the mechanism of signal transduction. (van et al., 1997) |
11113209, 10656590, 10.1007/BF01276808, 11038545 |
PLNlncRbase
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