Distinct expression patterns of ß-1,3-glucanases and
chitinases during the germination of Solanaceous seeds
| Luciana Petruzzelli, Kerstin Müller, Katrin Hermann, Gerhard
| Table 3. ß-1,3-Glucanase (ßGlu) and chitinase (Chn) activity
induction in imbibed Solanaceous seeds and in young seedlings.
(1) Rupture of the micropylar testa (seed coat) and rupture of the micropylar endosperm, i.e. radicle emergence, were distinct and temporally separate events during the germination of Cestroideae-type seeds.
(2) ABA inhibition of germination and ßGlu accumulation in the micropylar endosperm appears to be a widespread event during the seed germination of Solanaceous species.
(3) In contrast, accumulation of Chn and of distinct ßGlu isoforms in the embryo prior to germination appears to be a species-specific phenomenon within the Solanaceae.
(4) A post-germination co-induction of ßGlu and Chn in the root of the emerged seedling was found in endospermic and non-endospermic species and could represent an evolutionary conserved event during dicot seedling development.
A plus (+) sign means presence and a minus (-) sign absence of a feature or process; nd = not determined
* Localization of ßGlu induction in the micropylar part of the endosperm has been demonstrated.
** No inhibition by ABA of overall seed ßGlu activity accumulation, which does not per se exclude the existence of an ABA-responsive ßGlu isoform in the endosperm.
*** Co-induction of ßGlu and Chn in the seedling root appears to be an evolutionary conserved event during seedling development.
It is not only found in endospermic species, but also in non-endospermic species like pea (Petruzzelli et al 1999; Petruzzelli et al 2003a)
(1) Petruzzelli, Müller, Hermann, Leubner-Metzger. Seed Science Research 13: 139-153 (2003b)
(2) Kunz, Schöb, Leubner-Metzger, Glazov, Meins. Planta 212: 959-968 (2001)
(3) Wu, Leubner-Metzger, Meins, Bradford. Plant Physiology 126: 1299-1313 (2000)
(4) Leubner-Metzger, Fründt, Vögeli-Lange, Meins. Plant Physiology 109: 751-759 (1995)
(5) Vögeli-Lange, Fründt, Hart, Nagy, Meins. Plant Molecular Biology 25: 299-311 (1994)
(6) Krock, Schmidt, Hertweck, Baldwin. Seed Science Research 12: 239-252 (2002) and our own measurements.