| |
Downregulating determinants of satBaMV (09-22-2006) |
 |
|
| As obligate parasites, viruses can infect plants, animals and microorganisms. However, viruses can be also parasitized by a number of subviral agents, which entirely depend on the virus for replication and encapsidation. Satellite RNA, associated exclusively with plant viruses, is one of them, which can modify the helper virus replication and virus-induced symptoms in plants. Na-Sheng Lin's lab isolated two satellite RNAs associated with Bamboo mosaic virus (BaMV) from different bamboo species exhibit different phenotypes. SatBaMV isolate BSL6 (yellow) significantly reduces BaMV replication and suppresses the BaMV-induced symptoms in Nicotiana benthamiana plants whereas BSF4 (white) does not. Hypervariable (HV) region found in the 5' untranslated region (5' UTR) of many natural satBaMV isolates forms a conserved apical hairpin stem-loop (AHSL) structure. Interchanges of AHSL segment of HV regions between BSF4 and BSL6 led to the ability of chimeric satBaMV to interfere with BaMV replication and symptom expression (Hsu et al., 2006. J. Virol. 80: 2566-2574, Yeh et al., 2004. Virology 330:105-115, Hsu et al., 1998. Mol. Plant-Microbe Interact. 11: 1207-1213). |
|
|
|
| Iron deficiency triggers root cell morphogenesis (09-12-2006) |
 |
|
| As part of a multifaceted response to iron deficiency, root epidermal cells can differentiate into transfer cells, a cell type that is characterized by extensive cell-wall ingrowths. Transport proteins are polarized to membranes of distal tangential walls of epidermal transfer cells. The secrets of their induction are currently explored by Simonetta Santi and Wolfgang Schmidt at Rm 220 (A. Schikora, O. Thimm, B. Linke, T. J. Buckhout, M. Műller, W. Schmidt 2006. Expression, localization, and regulation of the iron transporter LeIRT1 in tomato roots. Plant and Soil, 284: 101-108). |
|
|
|
| Direct embryogenesis on Dendrobium's leaves (09-12-2006) |
| One more report on orchid embryo formation from Wei-chin Chang's Lab (HH Chung, JT Chen & WC Chang 2006 Plant regeneration through direct somatic embryogenesis from leaf explants of Dendrobium. Biol. Plant. In press). It's an ideal cell-to-plant system for transgenic attempts on this orchid. |
|
|
 |
|
|
 |
|
|
|
|
