Transcriptomic responses of Saccharum spontaneum roots in response to polyethylene glycol - 6000 stimulated drought stress.

Drought is the abiotic factor that adversely affects plant growth, development survival, and crop productivity, posing a substantial threat to sustainable agriculture worldwide, especially in warm and dry areas. However, the extent of damage depends upon the crop growth stage, severity and frequency of the stress. In general, the reproductive growth phase is more sensitive to stresses causing a substantial loss in crop productivity. Saccharum spontaneum (L.) is the most variable wild relative of sugarcane with potential for use in sugarcane crop improvement programs. In the present study addresses the transcriptomic analysis of drought stress imposed by polyethylene glycol-6000 (PED-6000; w/v- 25%) on the root tip tissues of S. spontaneum GX83-10. The analysis of microarrays of drought-stressed roots was performed at 0 (CK), 2 (T2), 4 (T4), 8 (T8) and 24 h (T24). The analyzed data were compared with the gene function annotations of four major databases, such as Nr, KOG/COG, Swiss-Prot, and KEGG, and a total of 62,988 single-gene information was obtained. The differently expressed genes of 56237 (T4), 59319 (T8), and 58583 (T24), among which CK obtained the most significant number of expressed genes (35920) as compared to T24, with a total of 53683 trend genes. Gene ontology (GO) and KEGG analysis were performed on the 6 important trends, and a total of 598 significant GO IDs and 42 significantly enriched metabolic pathways. Furthermore, these findings also aid in the selection of novel genes and promoters that can be used to potentially produce crop plants with enhanced stress resistance efficiency for sustainable agriculture.

AOP-1 interacts with cardiac-specific protein kinase TNNI3K and down-regulates its kinase activity.

In the present study, a yeast two-hybrid screening system was used to identify the interaction partners of cardiac troponin I-interacting kinase (TNNI3K) that might serve as regulators or targets, and thus in turn to gain some insights on the roles of TNNI3K. After screening the adult heart cDNA library with a bait construct encoding the ANK motif of TNNI3K, antioxidant protein 1 (AOP-1) was isolated. The interaction between TNNI3K and AOP-1 was confirmed by the in vitro binding assay and coexpression experiments in vivo. The colocalization of TNNI3K and AOP-1 was clarified by confocal immunofluorescence. Moreover, coexpression of AOP-1 inhibited TNNI3K kinase activity in the in vitro kinase assay.

Killing effect of coexpressing cytosine deaminase and thymidine kinase on rat vascular smooth muscle cells.

BACKGROUND: Vascular smooth muscle cell (VSMC) proliferation following arterial injury plays a critical role in a variety of vascular proliferative disorders, such as atherosclerosis and restenosis after balloon angioplasty. Herpes simplex virus-thymidine kinase (HSV-TK)/ganciclovir (GCV) and E. coli cytosine deaminase (CD)/5-fluorocytosine (5-Fc) suicide gene systems have been successfully employed in cardiovascular gene therapy, respectively. We reasoned that coexpression of both HSV-TK with CD suicide genes would lead to increased cell killing. To test this imagine, the adenoviral vectors expressing TK and/or CD genes were developed and tested on vascular smooth muscle cells. METHODS: Adenoviral vectors, including Ad-EF1alpha-CD-cytomegalovirus (CMV)-TK coexpressing both CD and TK double suicide genes, Ad-EF1alpha-CD and Ad-CMV-TK expressing CD and TK respectively, and control vector Ad-CMV-LacZ, were constructed and prepared with homologous recombination in RecA + E. coli cells. Integration and expression of CD and/or TK gene were identified by PCR and Western blot. Primary cultured VSMCs were infected at a multiplicity of infection (MOI) of 20 with exposure to their matching prodrugs 5-Fc and GCV. Cell mortality was measured by methyl thiazolyl tetrazolium (MTT) assays. Flow cytometry analysis was used to detect cell death. Apoptotic cells were analyzed using Hoechst 33342 fluorescence dye as a DNA probe. Genomic DNA cleavage of apoptotic VSMCs was tested by agarose gel electrophoresis. RESULTS: Recombinant adenovirus expressing CD and/or TK suicide genes were successfully constructed. Both single and double suicide genes could be integrated into adenoviral genome and expressed. Cytotoxic effects of Ad-EF1alpha-CD-CMV-TK double suicide genes combined with 5-Fc and GCV were higher than those of Ad-CMV-TK and Ad-EF1alpha-CD single gene groups. The rate of cell survival was only (9 +/- 3)% in the Ad-EF1alpha-CD-CMV-TK group, but (37 +/- 3)% in the Ad-CMV-TK and (46 +/- 4)% in the Ad-EF1alpha-CD groups (P < 0.05). Flow cytometry analysis indicated that the killing mechanisms of the groups were different. Necrosis and apoptosis were involved in the mechanism of the double gene group. Based on the DNA stainability with Hoechst 33342, the apoptotic rates of VSMCs in the Ad-EF1alpha-CD-CMV-TK [(11.0 +/- 2.1)%] and Ad-CMV-TK [(12.0 +/- 2.2)%] groups were higher than those in Ad-CMV-LacZ [(1.2 +/- 0.11)%] and Ad-EF1alpha-CD [(5.0 +/- 1.8)%] groups (P < 0.05, respectively). DNA smear could be observed in both Ad-CMV-TK and Ad-EF1alpha-CD-CMV-TK groups after administration of prodrugs. CONCLUSIONS: The killing effect on rat VSMCs mediated by adenoviral CD/TK double suicide genes is superior to that of single suicide gene. The killing mechanism of recombinant adenovirus coexpressing CD/TK double suicide genes is mainly through cytotoxic effect and apoptosis.

[Cloning and characterization of a novel cardiac-specific kinase gene p93 related to sarcomere].

Myocyte's contraction is regulated by signal transduction pathway composed with many protein factors, but the definite mechanism is still uncertain. A novel cardiac-specific kinase gene which participates in regulation of signal transduction, p93 named, was cloned from adult heart cDNA library. p93, coding a family member of MAPKKK, localized on 1p31.1 based on bioinformatics analyses. Northern blot and 76-tissue array analyses determined that p93 was merely expressed in heart, but was undetectable in other tissues. Immunohistochemical study showed that p93 predominantly localized in the nucleus of cardiac myocytes. In vitro kinase assay indicated that p93 was a functional kinase capable of autophosphorylation. p93 could directly interact with cardiac troponin I by yeast two-hybrid system assessed utilizing bait plasmid containing p93 C-terminus (733 835 aa) and results were further confirmed by co-immunoprecipitation in vivo. Our data suggest that p93 is a cardiac-specific kinase and may play important role in regulation of sarcomeric contraction protein with signal transduction pathway similar ILK.

Cloning and characterization of a novel cardiac-specific kinase that interacts specifically with cardiac troponin I.

Cardiac-restricted genes play important roles in cardiovascular system. In an effort to identify such novel genes we identified a novel cardiac-specific kinase gene TNNI3K localized on 1p31.1 based on bioinformatics analyses. Sequence analysis suggested that TNNI3K is a distant family member of integrin-linked kinase. Northern blot and 76-tissue array analyses showed that TNNI3K is highly expressed in heart, but is undetectable in other tissues. Immunohistochemical analysis predominantly localized TNNI3K in the nucleus of cardiac myocytes. In vitro kinase assay showed that TNNI3K is a functional kinase. The yeast two-hybrid system showed that TNNI3K could directly interact with cardiac troponin I, results that were further confirmed by coimmunoprecipitation in vivo. Our data suggest that TNNI3K is a cardiac-specific kinase and play important roles in cardiac system.

[Effect of antisense thrombin receptor and p21 double gene co-expression system on the proliferation and apoptosis in human aortic smooth muscle cells].

OBJECTIVE: To focus on the study of the effect on proliferation and apoptosis of human aortic smooth muscle cells (ASMC) by adeno-associated virus (AAV) vector carrying antisense thrombin receptor (ATR) and p21 double gene co-expression system. METHODS: Cultured human AMSC was infected with recombinant AAV containing ATR, p21 single gene and AP double gene respectively. The integration and expression of genes were confirmed by semi-quantitative RT-PCR. The anti-proliferation effect was determined by MTT assay. Cell cycle and apoptotic cell counts were measured through Flow Cytometry. The rate of apoptotic cells was examined with acridine orange/ethidium bromide(AO/EB) stain. RESULTS: RT-PCR indicated that the exogenous genes had been integrated into ASMC. The rates of cell survival were decreased by 16.67%, 21.60%, and 29.4% and the cell counts of G0/G1 phase were (61.8 +/- 2.9)%, (82.5 +/- 4.0)%, (80.4 +/- 6.1)% in ATR, p21 and AP group respectively after rAAV infected 4 days. The level and area of apoptotic peak were greater in AP double gene than ATR and p21 single gene. Cell stain indicated that apoptotic cells were (7.2 +/- 3.3)%, (10.7 +/- 5.6)%, and (18.3 +/- 2.7)% in each transgene group compared with (1.5 +/- 0.8)% in control group. CONCLUSION: AP double gene co-expression system has powerful effect for inhibiting proliferation and inducing apoptosis ASMC than ATR and p21 single gene and that is a superior way for gene therapy to restenosis.

Molecular Cloning of NELIN, a Putative Human Cytoskeleton Regulation Gene.

For searching cardiovascular-associated genes and investigating their expression profiles, human adult heart and aorta cDNA libraries were constructed, and a novel gene from adult heart cDNA library was isolated based on large-scale ESTs(expressed sequence tags) sequencing(GenBank accession number AF114264). The 2 736 bp clone contains one 1 344 bp open reading frame extending from 412 to 1 755. We named it NELIN (nexilin-like protein) because it shares high similarity with the rat nexilin. NELIN was expression-restricted in heart, skeletalmuscle, artery and vein by Northern blot and RT-PCR analyses, and mapped to chromosome 1p31-1p32 by database analyses. Based on domain structure, NELIN could regulate the formations of stress fibers,focal adhesion and its signaling complex, and even participates in the signal transduction in FAs(focal adhesions).