RESUMO
We report the efficacy of an aldose reductase (ALDRXV4) enzyme from Xerophyta viscosa Baker in enhancing the prospects of plant's survival under abiotic stress. Transgenic tobacco plants overexpressing ALDRXV4 cDNA showed alleviation of NaCl and mannitol-induced abiotic stress. The transgenic plants survived longer periods of water deficiency and salinity stress and exhibited improved recovery after rehydration as compared to the wild type plants. The increased synthesis of aldose reductase in transgenic plants correlated with reduced methylglyoxal and malondialdehyde accumulation and an elevated level of sorbitol under stress conditions. In addition, the transgenic lines showed better photosynthetic efficiency, less electrolyte damage, greater water retention, higher proline accumulation, and favorable ionic balance under stress conditions. Together, these findings suggest the potential of engineering aldose reductase levels for better performance of crop plants growing under drought and salt stress conditions.
Assuntos
Aldeído Redutase/genética , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Aldeído Pirúvico/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Aldeído Redutase/metabolismo , Secas , Germinação/genética , Manitol/metabolismo , Fotossíntese/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Potássio/metabolismo , Prolina/metabolismo , Salinidade , Plântula/genética , Plântula/metabolismo , Cloreto de Sódio/metabolismo , Sorbitol/metabolismo , Nicotiana/metabolismoRESUMO
Recurrent chondroblastoma with pulmonary and palatal metastasis is a rare occurrence. We report the cytological and histological findings of such a case in a 33 years old male, where the primary diagnosis of metastatic chondroblastoma was made on FNAC, which was later confirmed on histopathology. The present case highlights that, some chondroblastomas do exist, that are capable of pursuing a malignant course.
Assuntos
Condroblastoma/diagnóstico , Condroblastoma/patologia , Recidiva Local de Neoplasia , Adulto , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/patologia , Neoplasias Palatinas/patologia , Palato/patologiaRESUMO
A cDNA (1061 bp) Bj glyII was cloned from a mannitol induced library of Brassica juncea. It encoded a protein of 335 amino acids with a molecular weight of 36.52 kDa. The deduced amino acid sequence of the clone showed 92% and 56% identity with Pennisetum and rice glyoxalase II, respectively, and 30% identity was observed with the human glyoxalase II. Search for the identical residues revealed the presence of highly conserved THHHXDH domain which is involved in zinc binding. p-NN and pSORT analysis of this sequence revealed a N-terminal mitochondrial target peptide. The cDNA was cloned in pMAL and a fusion protein with MBP (78 kDa) was expressed in Escherichia coli. The recombinant protein was purified approximately sixfold by affinity purification on amylose column and showed its pH optima at 7.0. The K(m) was determined to be 120 microM using S-d-lactoylglutathione as substrate. The expression of Bj glyII under various abiotic stress conditions showed that it is upregulated by salinity, heavy metal stress, and ABA.
