Influence of Dexmedetomidine Applied in Combined Acupuncture-medication Anesthesia on Vomiting After Thyroidectomy / 上海针灸杂志

Objective To observe the influence of dexmedetomidine applied in combined acupuncture-medication anesthesia on vomiting after thyroidectomy. Method Seventy patients who were going to receive thyroidectomy were randomized into group A and B, with 35 cases in each group. Combined acupuncture-medication anesthesia [electroacupuncture at Hegu (LI4), Neiguan (PC6) and Futu (ST32) plus intravenous infusions of sufentanil citrate injection (0.3 mg/kg) 20 minutes before operation]was adopted in both groups. Group A was additionally intervened by constantvelocity micropump infusion of dexmedetomidine hydrochloride injection (0.5 mg/kg) within 10 minutes before operation and remaining 0.4 mg/kg/min during operation, while group B was intervened by infusion of normal saline 10 minutes before operation. The observer's assessment of awareness/sedation (OAA/S) scores at different time points[lying in bed for 5 minutes before operation (T0), before the beginning of the operation (T1), 30 minutes after operation (T2), 60 minutes after operation (T3) and at the end of operation (T4)] in the two groups were observed. The additional times and total dose of sufentanil during operation, the number of cases using esmolol and urapidil, and the number of vomiting cases occurred within 2 hours after operation and 2～24 hours after operation in the two groups were recorded.Result The additional times and total dose of sufentanil during operation in group A were significantly different from those in group B (P<0.01). The utilization rate of esmolol and urapidil were respectively 31.4％ and 14.3％ in group A versus 77.1％ and 65.7％ in group B, and the between-group differences were statistically significant (P<0.01). The incidence of vomiting within 2 hours after operation and 2～24 hours after operation were respectively 20.0％ and 17.1％in group A versus 54.3％ and 42.9％ in group B, and the between-group differences were statistically significant (P<0.01). The OAA/S scores at different time points (T1, T2, T3 and T4) in group A were significantly different from those in group B (P<0.01). Conclusion Dexmedetomidine applied in combined acupuncture-medication anesthesia can reduce the additional times and total dose of sufentanil during thyroidectomy, and it can reduce the incidence of postoperative vomiting as well.

Effect of receptor tyrosine phosphatase D on the characteristics of breast cancer stem cells / 临床与实验病理学杂志

Purpose To investigate the effect of protein tyrosine phosphatase receptor type D (PTPRD) on the characteristics of breast cancer stem cells. Method PTPRD expression in breast cancer cell line MDA-MB231 was down-regulated by small interference RNAs (siRNAs). Self-renewal ability of breast cancer stem cells (BCSCs) was detected by mammosphere formation assay. The holocolony forming ability was detected by colony formation assay. The proportion of CD44+/CD24- BCSCs was detected by flow cytometry. The ability of tumorigenesis of breast cancer cells in mice was sdudied with mouse tumorigenesis test. Separation of CD44+/CD24- stem cell population and non-stem cell population was isolated by immunomagnetic beads. Expression of PTPRD in stem cell and non-stem cell population was detected by Western blot and immunofluorescent. Results Down-regulation of PTPRD promoted the expression of stem cell markers ALDH1 and OCT-4. The expression of PTPRD in breast cancer stem cells was lower than than in non-stem cells (P<0.05). After PTPRD was down-regulated, the number of mammosphere (147±3.51) was significantly higher than that of the control group (106±12.5) (P<0.05), the proportion of holoclone [(35.9±3.4) ％] was significantly higher than that of the control group [(11.2±5.3) ％] (P<0.05), the proportion of CD44+/CD24- cells[(2.88±1.2) ％]was significantly higher than that of the control group [(0.6±0.4) ％], the in vivo tumorigenicity was significantly enhanced in nude mice (P<0.05). Conclusion The expression of PTPRD is lower in BCSCs. PTPRD may inhibit the self-renewal ability of breast cancer stem cells.

A High-Density Genetic Linkage Map for Cucumber (Cucumis sativus L.): Based on Specific Length Amplified Fragment (SLAF) Sequencing and QTL Analysis of Fruit Traits in Cucumber.

High-density genetic linkage map plays an important role in genome assembly and quantitative trait loci (QTL) fine mapping. Since the coming of next-generation sequencing, makes the structure of high-density linkage maps much more convenient and practical, which simplifies SNP discovery and high-throughput genotyping. In this research, a high-density linkage map of cucumber was structured using specific length amplified fragment sequencing, using 153 F2 populations of S1000 × S1002. The high-density genetic map composed 3,057 SLAFs, including 4,475 SNP markers on seven chromosomes, and spanned 1061.19 cM. The average genetic distance is 0.35 cM. Based on this high-density genome map, QTL analysis was performed on two cucumber fruit traits, fruit length and fruit diameter. There are 15 QTLs for the two fruit traits were detected.

Transcriptome Analyses Reveal the Involvement of Both C and N Termini of Cryptochrome 1 in Its Regulation of Phytohormone-Responsive Gene Expression in Arabidopsis.

Cryptochromes (CRY) are blue-light photoreceptors that mediate various light responses in plants and animals. It has long been demonstrated that Arabidopsis CRY (CRY1 and CRY2) C termini (CCT1 and CCT2) mediate light signaling through direct interaction with COP1. Most recently, CRY1 N terminus (CNT1) has been found to be involved in CRY1 signaling independent of CCT1, and implicated in the inhibition of gibberellin acids (GA)/brassinosteroids (BR)/auxin-responsive gene expression. Here, we performed RNA-Seq assay using transgenic plants expressing CCT1 fused to ß-glucuronidase (GUS-CCT1, abbreviated as CCT1), which exhibit a constitutively photomorphogenic phenotype, and compared the results with those obtained previously from cry1cry2 mutant and the transgenic plants expressing CNT1 fused to nuclear localization signal sequence (NLS)-tagged YFP (CNT1-NLS-YFP, abbreviated as CNT1), which display enhanced responsiveness to blue light. We found that 2903 (67.85%) of the CRY-regulated genes are regulated by CCT1 and that 1095 of these CCT1-regulated genes are also regulated by CNT1. After annotating the gene functions, we found that CCT1 is involved in mediating CRY1 regulation of phytohormone-responsive genes, like CNT1, and that about half of the up-regulated genes by GA/BR/auxin are down-regulated by CCT1 and CNT1, consistent with the antagonistic role for CRY1 and these phytohormones in regulating hypocotyl elongation. Physiological studies showed that both CCT1 and CNT1 are likely involved in mediating CRY1 reduction of seedlings sensitivity to GA under blue light. Furthermore, protein expression studies demonstrate that the inhibition of GA promotion of HY5 degradation by CRY1 is likely mediated by CCT1, but not by CNT1. These results give genome-wide transcriptome information concerning the signaling mechanism of CRY1, unraveling possible involvement of its C and N termini in its regulation of response of GA and likely other phytohormones.

DELLA proteins physically interact with CONSTANS to regulate flowering under long days in Arabidopsis.

Proper timing of flowering is essential for reproduction of plants. Although it is well known that both light and gibberellin (GA) signaling play critical roles in promoting flowering in Arabidopsis thaliana, whether and how they are integrated to regulate flowering remain largely unknown. Here, we show through biochemical studies that DELLA proteins physically interact with CONSTANS (CO). Furthermore, the interaction of CO with NF-YB2 is inhibited by the DELLA protein, RGA. Our findings suggest that regulation of flowering by GA signaling in leaves under long days is mediated, at least in part, through repression of DELLA proteins on CO, providing a molecular link between DELLA proteins, key components in GA signaling pathway, and CO, a critical flowering activator in photoperiod signaling pathway.

Micro-trichome as a class I homeodomain-leucine zipper gene regulates multicellular trichome development in Cucumis sativus.

Plant trichomes serve as a highly suitable model for investigating cell differentiation at the single-cell level. The regulatory genes involved in unicellular trichome development in Arabidopsis thaliana have been intensively studied, but genes regulating multicellular trichome development in plants remain unclear. Here, we characterized Cucumis sativus (cucumber) trichomes as representative multicellular and unbranched structures, and identified Micro-trichome (Mict), using map-based cloning in an F2 segregating population of 7,936 individuals generated from a spontaneous mict mutant. In mict plants, trichomes in both leaves and fruits, are small, poorly developed, and denser than in the wild type. Sequence analysis revealed that a 2,649-bp genomic deletion, spanning the first and second exons, occurred in a plant-specific class I homeodomain-leucine zipper gene. Tissue-specific expression analysis indicated that Mict is strongly expressed in the trichome cells. Transcriptome profiling identified potential targets of Mict including putative homologs of genes known in other systems to regulate trichome development, meristem determinacy, and hormone responsiveness. Phylogenic analysis charted the relationships among putative homologs in angiosperms. Our paper represents initial steps toward understanding the development of multicellular trichomes.

Red-light-dependent interaction of phyB with SPA1 promotes COP1-SPA1 dissociation and photomorphogenic development in Arabidopsis.

Arabidopsis phytochromes (phyA-phyE) are photoreceptors dedicated to sensing red/far-red light. Phytochromes promote photomorphogenic developments upon light irradiation via a signaling pathway that involves rapid degradation of PIFs (PHYTOCHROME INTERACTING FACTORS) and suppression of COP1 (CONSTITUTIVE PHOTOMORPHOGENIC 1) nuclear accumulation, through physical interactions with PIFs and COP1, respectively. Both phyA and phyB, the two best characterized phytochromes, regulate plant photomorphogenesis predominantly under far-red light and red light, respectively. It has been demonstrated that SPA1 (SUPPRESSOR OF PHYTOCHROME A 1) associates with COP1 to promote COP1 activity and suppress photomorphogenesis. Here, we report that the mechanism underlying phyB-promoted photomorphogenesis in red light involves direct physical and functional interactions between red-light-activated phyB and SPA1. We found that SPA1 acts genetically downstream of PHYB to repress photomorphogenesis in red light. Protein interaction studies in both yeast and Arabidopsis demonstrated that the photoactivated phyB represses the association of SPA1 with COP1, which is mediated, at least in part, through red-light-dependent interaction of phyB with SPA1. Moreover, we show that phyA physically interacts with SPA1 in a Pfr-form-dependent manner, and that SPA1 acts downstream of PHYA to regulate photomorphogenesis in far-red light. This study provides a genetic and biochemical model of how photoactivated phyB represses the activity of COP1-SPA1 complex through direct interaction with SPA1 to promote photomorphogenesis in red light.

Jasmonic acid enhancement of anthocyanin accumulation is dependent on phytochrome A signaling pathway under far-red light in Arabidopsis.

Anthocyanins are critical for plants. It is shown that the expression of genes encoding the key enzymes such as dihydroflavonol 4-reductase (DFR), UDP-Glc: flavonoid 3-O-glucosyltransferase (UF3GT), and leucoanthocyanidin dioxygenase (LDOX) in anthocyanin biosynthesis pathway is regulated by MYB75, a R2R3 MYB transcription factor. The production of anthocyanin is known to be promoted by jasmonic acid (JA) in light but not in darkness. The photoreceptors cryptochrome 1 (CRY1), phytochrome B (phyB), and phytochrome A (phyA) are also shown to mediate light promotion of anthocyanin accumulation, respectively, whereas their downstream factor COP1, a master negative regulator of photomorphogensis, represses anthocyanin accumulation. However, whether JA coordinates with photoreceptors in the regulation of anthocyanin accumulation is unknown. Here, we show that under far-red light, JA promotes anthocyanin accumulation in a phyA signaling pathway-dependent manner. The phyA mutant is hyposensitive to jasmonic acid analog methyl jasmonic acid (MeJA) under far-red light. The dominant mutant of MYB75, pap1-D, accumulates significantly higher levels of anthocyanin than wild type under far-red light, whereas knockdown of MYBs (MYB75, MYB90, MYB113, and MYB114) through RNAi significantly reduces MeJA promotion of anthocyanin accumulation. The phyA pap1-D double mutant shows reduced responsiveness to MeJA, similar to phyA mutant under far-red light. In darkness, a mutant allele of cop1, cop1-4, shows enhanced responsiveness to MeJA, but pap1-D mutant is barely responsive to MeJA. Upon MeJA application, the cop1-4 pap1-D double mutant accumulates considerably higher levels of anthocyanin than cop1-4 in darkness. Protein studies indicate that MYB75 protein is stabilized by white light and far-red light. Further gene expression studies suggest that MeJA promotes the expression of DFR, UF3GT, and LDOX genes in a phyA- and MYB75-dependent manner under far-red light. Our findings suggest that JA promotion of anthocyanin accumulation under far-red light is dependent on phyA signaling pathway, consisting of phyA, COP1, and MYB75.

COP1 and phyB Physically Interact with PIL1 to Regulate Its Stability and Photomorphogenic Development in Arabidopsis.

In Arabidopsis thaliana, the cryptochrome and phytochrome photoreceptors act together to promote photomorphogenic development. The cryptochrome and phytochrome signaling mechanisms interact directly with CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1), a RING motif-containing E3 ligase that acts to negatively regulate photomorphogenesis. COP1 interacts with and ubiquitinates the transcription factors that promote photomorphogenesis, such as ELONGATED HYPOCOTYL5 and LONG HYPOCOTYL IN FAR-RED1 (HFR1), to inhibit photomorphogenic development. Here, we show that COP1 physically interacts with PIF3-LIKE1 (PIL1) and promotes PIL1 degradation via the 26S proteasome. We further demonstrate that phyB physically interacts with PIL1 and enhances PIL1 protein accumulation upon red light irradiation, probably through suppressing the COP1-PIL1 association. Biochemical and genetic studies indicate that PIL1 and HFR1 form heterodimers and promote photomorphogenesis cooperatively. Moreover, we demonstrate that PIL1 interacts with PIF1, 3, 4, and 5, resulting in the inhibition of the transcription of PIF direct-target genes. Our results reveal that PIL1 stability is regulated by phyB and COP1, likely through physical interactions, and that PIL1 coordinates with HFR1 to inhibit the transcriptional activity of PIFs, suggesting that PIL1, HFR1, and PIFs constitute a subset of antagonistic basic helix-loop-helix factors acting downstream of phyB and COP1 to regulate photomorphogenic development.

Efficacy on analgesia with electric stimulation of long-term retaining needle after laparoscopic cholecystectomy / 中国针灸

<p><b>OBJECTIVE</b>To observe the clinical effect of electric stimulation of long-term retaining needle on analgesia after laparoscopic cholecystectomy (LC) and the impacts on the post-surgical flatus time.</p><p><b>METHODS</b>Under static absorptive composite general anesthesia, 90 cases of LC were randomized into three groups, 30 cases in each one. In the control group, the analgesia was not applied after LC. In the analgesia-pumper group, the patient controlled intravenous analgesia (PCIA) was used. In the needle-retaining group, the electric acupuncture stimulator was used. The needles were inserted transversely at Riyue (GB 24), Qichong (ST 30) and Yanglingquan (GB 34) and fixed with sterile sticker. Separately, in 8 h and 24 h after surgery, the electric acupuncture stimulation with disperse-dense wave, 2 Hz/100 Hz frequency was applied continuously for 30 min. Visual analogue scale (VAS), adverse reactions such as vomiting and nausea and the postoperative flatus time in 2, 4, 8, 12, 24 and 36 h after surgery were observed and recorded in the three groups.</p><p><b>RESULTS</b>In 2, 4, 8, 12 and 24 h after surgery, VAS scores in the needle-retaining group and the analgesia-pumper group were all lower than those in the control group (P < 0.05, P < 0.01). The analgesia effect at the above time points in the needle-retaining group was better than that in the analgesia-pumper group (all P < 0.05). There was not adverse reaction in the needle-retaining group. But there were 3 cases of somnolence, 6 cases of nausea and 3 cases of vomiting in the analgesia-pumper group, and 2 cases of nausea and 1 case of vomiting in the control group. The flatus time was quite earlier in the needle-retaining group as compared with the other two groups [(14.77 +/- 4.99) h vs (18.50 +/- 4.22) h, P < 0.01; (14.77 +/- 4.99) h vs (18.17 +/- 4.69) h, P < 0.05].</p><p><b>CONCLUSION</b>The electric stimulation of long-term retaining needle is safe and effective in analgesia after LC. It avoids the adverse reactions of analgesics and promotes postoperative flatus.</p>

Down-regulation of Smoothened gene expression inhibits proliferation of breast cancer stem cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the influence of down-regulating Smoothened (SMO) gene expression through short hairpin RNA (shRNA) on the proliferation of breast cancer stem cells.</p><p><b>METHODS</b>Human SMO shRNA was designed, synthesized chemically, and transfected into MCF-7 cells to down-regulate SMO gene. By using G418, stable cells with down-regulated SMO were selected. In vitro proliferation of these cells was measured by CCK8 assay. The proportion of CD44(+)/CD24(-) cells was detected by flow cytometry and the mammospheres formation was determined by suspension sphere culture. The expression of SMO, GLI1 and Oct4 was detected by Western blot. In vivo, the volume of tumor was measured every 3 days and the expression of SMO, GLI1 and Oct4 detected by Western blot.</p><p><b>RESULTS</b>In vitro, the cells were transfected with SMO-shRNA and selected by G418 after 21 days. SMO-shRNA effectively down-regulated the expression of SMO gene and protein, and inhibited the proliferation of MCF-7 and markedly reduced the proportion of CD44(+)/CD24(-) cells and mammospheres. In vivo, SMO-shRNA treatment of MCF-7 significantly inhibited the volume of tumor. The positive rate of SMO in negative control and SMO-shRNA group was 5/5 and 2/5, respectively. The expression of SMO, GLI1 and Oct4 in different groups were 0.72 ± 0.17 and 0.21 ± 0.09, 1.21 ± 0.21 and 0.47 ± 0.12, 0.83 ± 0.13 and 0.25 ± 0.07. SMO, GLI1 and Oct4 down-regulation significantly suppressed at protein levels (P < 0.05).</p><p><b>CONCLUSION</b>The shRNA by chemical synthesis can effectively down-regulate SMO gene expression and inhibit the proliferation of breast cancer stem cells.</p>

Blue-light-dependent interaction of cryptochrome 1 with SPA1 defines a dynamic signaling mechanism.

Cryptochromes (CRYs) are blue-light photoreceptors that mediate various light responses in plants and animals. The signaling mechanism by which CRYs regulate light responses involves their physical interactions with COP1. Here, we report that CRY1 interacts physically with SPA1 in a blue-light-dependent manner. SPA acts genetically downstream from CRYs to regulate light-controlled development. Blue-light activation of CRY1 attenuates the association of COP1 with SPA1 in both yeast and plant cells. These results indicate that the blue-light-triggered CRY1-SPA1 interaction may negatively regulate COP1, at least in part, by promoting the dissociation of COP1 from SPA1. This interaction and consequent dissociation define a dynamic photosensory signaling mechanism.

Phytochrome B is involved in mediating red light-induced stomatal opening in Arabidopsis thaliana.

The stomatal pores of higher plants enable gaseous exchange into and out of leaves for photosynthesis and evaporation. Stomatal opening is induced by both blue and red lights. It is shown that blue light-induced stomatal opening is mediated by the blue light receptor phototropins (PHOT1 and PHOT2) and cryptochromes (CRY1 and CRY2). However, whether phytochrome B (phyB) is involved in red light regulation of stomatal opening remains largely unclear. Here, we report a positive role for Arabidopsis (Arabidopsis thaliana) phyB in the regulation of red light-induced stomatal opening. The phyB mutant stomata displayed a reduced red light response, whereas stomata of the phyB-overexpressing plants displayed a hypersensitive response to red light. In addition, stomata of the cry1 cry2 phyB, phot1 phot2 phyB, and cry1 phyA phyB triple mutant plants showed more reduced light response than those of the single or double mutant plants under white light, implying that phyB acts in concert with phyA, CRY, and PHOT in light regulation of stomatal opening. Stomata of phyB cop1 mutant opened less wide than those of the cop1 mutant, and stomata of the pif3 pif4 mutant opened wider than those of the wild-type, indicating that COP1, together with the PIFs (phytochrome interacting factors), may act downstream of PHYB in regulating stomatal opening. Furthermore, quantitative RT-PCR analysis showed that the expression of MYB60 was reduced in the cry1 cry2 and phyA phyB mutants under blue and red lights, respectively, but induced in the CRY1- and phyB-overexpressing plants. These results demonstrate that phyB and CRY might regulate stomatal opening, at least in part, by regulating MYB60 expression.

Expression of chromogranin A in human mammary tissues / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the pathogenesis and significance of neuroendocrine breast carcinoma by detecting chromogranin A (CgA) in human mammary tissues.</p><p><b>METHOD</b>Eighty-nine cases of human mammary tissues were collected to detect CgA expression using immunohistochemistry.</p><p><b>RESULT</b>No CgA expression was detected in normal or hyperplastic tissues, but its expression was found in mammary carcinoma tissues at the rate of 16.7%. A significant difference in CgA expression was found between cancer tissues and non-cancer tissues, but not between the cancer tissues with different pathological grades.</p><p><b>CONCLUSION</b>The pathogenesis of mammary neuroendocrine carcinoma may involve the micro-environmental factors that affect the differentiation of stem cells to give rise to immature cells, cell differentiation in other lineages or transdifferentiation. CgA may serve as an immunological parameter for this type of breast cancer in routine screening test.</p>

Cryptochromes, phytochromes, and COP1 regulate light-controlled stomatal development in Arabidopsis.

In Arabidopsis thaliana, the cryptochrome (CRY) blue light photoreceptors and the phytochrome (phy) red/far-red light photoreceptors mediate a variety of light responses. COP1, a RING motif-containing E3 ubiquitin ligase, acts as a key repressor of photomorphogenesis. Production of stomata, which mediate gas and water vapor exchange between plants and their environment, is regulated by light and involves phyB and COP1. Here, we show that, in the loss-of-function mutants of CRY and phyB, stomatal development is inhibited under blue and red light, respectively. In the loss-of-function mutant of phyA, stomata are barely developed under far-red light. Strikingly, in the loss-of-function mutant of either COP1 or YDA, a mitogen-activated protein kinase kinase kinase, mature stomata are developed constitutively and produced in clusters in both light and darkness. CRY, phyA, and phyB act additively to promote stomatal development. COP1 acts genetically downstream of CRY, phyA, and phyB and in parallel with the leucine-rich repeat receptor-like protein TOO MANY MOUTHS but upstream of YDA and the three basic helix-loop-helix proteins SPEECHLESS, MUTE, and FAMA, respectively. These findings suggest that light-controlled stomatal development is likely mediated through a crosstalk between the cryptochrome-phytochrome-COP1 signaling system and the mitogen-activated protein kinase signaling pathway.

Role of the aquaporin PIP1 subfamily in the chilling tolerance of rice.

Although an association between chilling tolerance and aquaporins has been reported, the exact mechanisms involved in this relationship remain unclear. We compared the expression profiles of aquaporin genes between a chilling-tolerant and a low temperature-sensitive rice variety using real-time PCR and identified seven genes that closely correlated with chilling tolerance. Chemical treatment experiments, by which rice plants were induced to lose their chilling tolerance, implicated the PIP1 (plasma membrane intrinsic protein 1) subfamily member genes in chilling tolerance. Of these members, changes in expression of the OsPIP1;3 gene suggested this to be the most closely related to chilling tolerance. Although OsPIP1;3 showed a much lower water permeability than members of the OsPIP2 family, OsPIP1;3 enhanced the water permeability of OsPIP2;2 and OsPIP2;4 when co-expressed with either of these proteins in oocytes. Transgenic rice plants (OE1) overexpressing OsPIP1;3 showed an enhanced level of chilling tolerance and the ability to maintain high OsPIP1;3 expression levels under low temperature treatment, similar to that of chilling-tolerant rice plants. We assume that OsPIP1;3, constitutively overexpressed in the leaf and root of transgenic OE1 plants, interacts with members of the OsPIP2 subfamily, thereby improving the plants' water balance under low temperatures and resulting in the observed chilling tolerance of the plants.

COP1-mediated ubiquitination of CONSTANS is implicated in cryptochrome regulation of flowering in Arabidopsis.

In Arabidopsis thaliana, the blue light photoreceptor cryptochromes (CRY) act to promote photomorphogenic development and the transition from vegetative to floral development in long days (LDs). We previously proposed that one of the mechanisms by which CRY regulates light responses is via its physical interaction with COP1, a RING motif-containing E3 ligase. Under LDs, the transcription of FLOWERING LOCUS T (FT) is activated by CONSTANS (CO) in leaf, and the FT protein moves to the shoot apex to induce flowering. CO protein is degraded in darkness, whereas it is stabilized by the CRY-mediated signal. However, the mechanism underlying this process is unknown. We show in this report that CO acts genetically downstream of COP1 and CRY to regulate flowering time. In addition, COP1 physically interacts with CO and functions as an E3 ligase, ubiquitinating CO in vitro and reducing CO levels in vivo. These results suggest that COP1 acts as a repressor of flowering by promoting the ubiquitin-mediated proteolysis of CO in darkness and that CRY-mediated signal may negatively regulate COP1, thereby stabilizing CO, activating FT transcription, and inducing flowering.

Upland rice and lowland rice exhibited different PIP expression under water deficit and ABA treatment.

Aquaporins play a significant role in plant water relations. To further understand the aquaporin function in plants under water stress, the expression of a subgroup of aquaporins, plasma membrane intrinsic proteins (PIPs), was studied at both the protein and mRNA level in upland rice (Oryza sativa L. cv. Zhonghan 3) and lowland rice (Oryza sativa L. cv. Xiushui 63) when they were water stressed by treatment with 20% polyethylene glycol (PEG). Plants responded differently to 20% PEG treatment. Leaf water content of upland rice leaves was reduced rapidly. PIP protein level increased markedly in roots of both types, but only in leaves of upland rice after 10 h of PEG treatment. At the mRNA level, OsPIP1;2, OsPIP1;3, OsPIP2;1 and OsPIP2;5 in roots as well as OsPIP1;2 and OsPIP1;3 in leaves were significantly up-regulated in upland rice, whereas the corresponding genes remained unchanged or down-regulated in lowland rice. Meanwhile, we observed a significant increase in the endogenous abscisic acid (ABA) level in upland rice but not in lowland rice under water deficit. Treatment with 60 microM ABA enhanced the expression of OsPIP1;2, OsPIP2;5 and OsPIP2;6 in roots and OsPIP1;2, OsPIP2;4 and OsPIP2;6 in leaves of upland rice. The responsiveness of PIP genes to water stress and ABA were different, implying that the regulation of PIP genes involves both ABA-dependent and ABA-independent signaling pathways during water deficit.