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G An

Publications and source records attributed to G An.

At least 37 records · Page 2Linked to original sources
PubMed1999

Isolation and characterization of an anther-specific gene, RA8, from rice (Oryza sativa L.).

An anther-specific cDNA clone of rice, RA8, was isolated from an anther cDNA library by differential screening. RNA blot analysis indicated that the RA8 transcript is present specifically in anthers and the transcript level increased as flowers matured, reaching the highest level in mature flowers. The RA8 clone contains an open reading frame of 264 amino acid residues with a hydrophobic N-terminal region. The deduced amino acid sequences did not show significant homology to any known sequences. Genomic DNA blot analysis showed that RA8 is a single-copy gene. A genomic clone corresponding to the RA8 cDNA was isolated and its promoter region was fused to the beta-glucuronidase (GUS) gene. Transgenic rice plants exhibited anther-specific expression of the GUS reporter gene. Histochemical GUS analysis showed that the RA8 promoter was active in the tapetum, endothecium, and connective tissues of anthers. Experiments showed that expression of the gene starts when microspores are released from tetrads, and it reaches to the maximum level at the late vacuolated-pollen stage. The RA8 promoter may be useful for controlling gene expression in anthers of cereal plants and for generating male-sterile plants.

Amino Acid Sequence↗
PubMed1999

Analysis of the C-terminal region of Arabidopsis thaliana APETALA1 as a transcription activation domain.

APETALA1 (AP1) of Arabidopsis thaliana is a transcription factor controlling flower development. AP2 is a member of the MADS (MCM1, AGAMOUS, DEFICIENS, SRF) superfamily, which plays important roles in differentiation in plants and animals. MADS domains, which function most importantly in DNA binding, are found in all major eukaryotic kingdoms. In plants, MADS domain-containing proteins also possess a region of moderate sequence similarity named the K domain, which is involved in protein-protein interaction. Little is known about the function of a third, highly variable, domain designated the C domain, as it resides at the C terminus of the MADS proteins of plants. Here we report that the C-terminal domain of Arabidopsis thaliana AP1 and its homologues perform a transcriptional activation function. The C-terminal region of AP1 is composed of at least two separable transcriptional activation domains that function synergistically.

Amino Acid Sequence↗
PubMed1999

Identification of a rice APETALA3 homologue by yeast two-hybrid screening.

A cDNA clone OsMADS16 was isolated from the rice young inflorescence cDNA expression library by the yeast two-hybrid screening method with OsMADS4 as bait. We have previously shown that the OsMADS4 gene is a member of the PI family and that the MADS-box gene is involved in controlling development of the second and third whorls of rice flowers. The sequence comparison indicated that OsMADS16 belongs to the AP3 family. The OsMADS16 protein contains a PI-derived motif, FAFRVVPSQPNLH, that is a conserved sequence in AP3 family genes at the C-terminal region. In addition, OsMADS16 contains a paleoAP3 motif, YGGNHDLRLG, downstream of the PI-derived motif. The paleoAP3 motif is a consensus sequence in the C-terminal region of the AP3 family genes of lower eudicot and magnolid dicot species. RNA blot analysis showed that the OsMADS16 gene was expressed in the second and third whorls, whereas the OsMADS4 transcripts were present in the second, third, and fourth whorls. These expression patterns of the OsMADS16 and OsMADS4 genes are very similar to those of AP3 and PI, respectively. In the yeast two-hybrid system, OsMADS4 interacted only with OsMADS16 among several rice MADS genes investigated, suggesting that OsMADS4 and OsMADS16 function as a heterodimer in specifying sepal and petal identities. The OsMADS16 protein displayed transcription activation ability in yeast, whereas AP3 did not. It was also shown in yeast that OsMADS16 interacted with PI whereas OsMADS4 did not interact with AP3. These differences between OsMADS16 and AP3 indicate that the functions of the AP3 family genes of monocots and dicots diverged during molecular evolution processes of the B function genes. Deletion analysis showed that the 155-200 amino acid region of the OsMADS16 protein plays an important role in the transcription activation ability.

Amino Acid Sequence↗
PubMed1999

Observation of the correlation of postanaesthesia recovery scores with early postoperative hypoxaemia in children.

To observe the correlation of the postanaesthesia recovery score (PARS) with the incidence, and severity of early postoperative hypoxaemia in children, 1213 infants and children, ASA physical status I, aged three months to 14 years, scheduled for elective plastic surgery were included in this study. Arterial oxygen saturation (Spo2) levels were recorded while children were breathing room air shortly after arrival in the recovery room (0 min), and 5, 10, 15, 20, 30, 40, 50, 60, 120 and 180 min thereafter. The PARS was also determined on all patients when Spo2 levels were recorded in the recovery room. On the basis of different PARS, children were divided into the three groups: Group 1-children having the PARS of < or = 6; Group 2-children having the PARS of 7-9; and Group 3-children having a PARS of 10. The results showed that during the early postoperative period, the incidence and severity of hypoxaemia correlated closely with the PARS. The lower the children's PARS, the higher the incidences of hypoxaemia (Spo2 = 86-90%) and severe hypoxaemia (Spo2 < or = 85%). The incidences of hypoxaemia and severe hypoxaemia were 12.9% and 15.8%, respectively, in Group 1, 20.9% and 2.9% in Group 2, 0.8% and 0% in Group 3. There were significant differences among the three groups. Of the 91 children who required O2 supplementation in the recovery room because of low measured Spo2, 69 had the PARS of < or = 6, and 22 had the PARS of 7-8. It is concluded that if a patient has a PARS of 10, the patient will not need routine oxygen supplement because hypoxaemia will not occur.

Adolescent↗
PubMed1999

The influence of surgical sites on early postoperative hypoxemia in adults undergoing elective surgery.

UNLABELLED: To determine the influence of the surgical sites on early postoperative hypoxemia, we studied postoperative hypoxemia in 994 patients, ASA physical status I or II, aged 18-68 yr, scheduled for various types of elective surgery. Patients were divided into three groups on the basis of the surgical sites: Group 1 = elective superficial plastic surgery (n = 288); Group 2 = upper abdominal surgery (n = 452); and Group 3 = thoracoabdominal surgery (n = 254). Anesthesia was maintained with 1%-2% enflurane and 67% nitrous oxide in oxygen; thiopental or fentanyl was given IV as required. SpO2 levels were recorded while patients breathed room air shortly after arrival in the recovery room (0 min) and 5, 10, 15, 20, 30, 40, 50, 60, 120, and 180 min thereafter. The results showed that during the early postoperative period, the degree of arterial desaturation and the incidences of hypoxemia (SpO2 86%-90%) and severe hypoxemia (SpO2 85%) were closely related to the operative sites and were greatest for thoracoabdominal operations, less for the upper abdominal operation, and least for the peripheral surgery. The incidence of hypoxemia and severe hypoxemia in the recovery room was 7% and 0.7%, respectively, in Group 1, 38% and 3% in Group 2, and 52% and 20% in Group 3. Mild airway obstruction and hypothermia in the postanesthesia recovery unit (PAR) were the predictive factors of early postoperative hypoxemia. We conclude that during the early postoperative period, there were significant differences in SpO2 levels and incidences of hypoxemia and severe hypoxemia among the three groups. IMPLICATIONS: We found that the severity of arterial desaturation and the incidence of hypoxemia during the early postoperative period are closely related to the surgical sites and are strongest for thoracoabdominal surgery, less for upper abdominal surgery, and least for peripheral surgery.

Abdomen↗
PubMed1999

Evisceration after abdominal stab wounds: is laparotomy required?

OBJECTIVES: To determine the incidence of intra-abdominal injury requiring laparotomy after an abdominal stab wound with evisceration. To identify clinical signs that increase the likelihood of an intra-abdominal injury in the presence of such a wound. METHODS: Information was collected prospectively over an 8-year period on all patients who presented to our urban level I trauma center with an abdominal stab wound and evisceration. This information included which organ eviscerated, presence of other indications for laparotomy, organs injured, and postoperative complications. All comparisons used the Fisher's exact chi2. RESULTS: A total of 81 patients were admitted with evisceration after an abdominal stab wound. Sixty-one patients (75%) had eviscerated omentum, 18 patients (22%) had eviscerated small bowel, and 2 patients (2%) had eviscerated colon. Sixty-two patients (76%) had evisceration as the sole indication for laparotomy, the remaining 19 patients (24%) had another indication such as hypotension or peritonitis. Overall, 63 patients (78%) had an intra-abdominal injury that required repair. This was true regardless of organ eviscerated (omentum = 77% vs. viscus = 80%, not significant) or clinical presentation (no other indication = 76% vs. another indication = 84%, not significant). CONCLUSION: The majority of patients who present with an evisceration after a stab wound to the abdomen require a laparotomy. This is true regardless of what has eviscerated or the presence of other clinical indications to operate. Evisceration should continue to prompt operative intervention.

Abdominal Injuries↗
PubMed1999

Determination of the motif responsible for interaction between the rice APETALA1/AGAMOUS-LIKE9 family proteins using a yeast two-hybrid system.

A MADS family gene, OsMADS6, was isolated from a rice (Oryza sativa L.) young flower cDNA library using OsAMDS1 as a probe. With this clone, various MADS box genes that encode for protein-to-protein interaction partners of the OsMADS6 protein were isolated by the yeast two-hybrid screening method. On the basis of sequence homology, OsMADS6 and the selected partners can be classified in the APETALA1/AGAMOUS-LIKE9 (AP1/AGL9) family. One of the interaction partners, OsMADS14, was selected for further study. Both genes began expression at early stages of flower development, and their expression was extended into the later stages. In mature flowers the OsMADS6 transcript was detectable in lodicules and also weakly in sterile lemmas and carpels, whereas the OsMADS14 transcript was detectable in sterile lemmas, paleas/lemmas, stamens, and carpels. Using the yeast two-hybrid system, we demonstrated that the region containing of the 109th to 137th amino acid residues of OsMADS6 is indispensable in the interaction with OsMADS14. Site-directed mutation analysis revealed that the four periodical leucine residues within the region are essential for this interaction. Furthermore, it was shown that the 14 amino acid residues located immediately downstream of the K domain enhance the interaction, and that the two leucine residues within this region play an important role in that enhancement.

Amino Acid Sequence↗
PubMed1999

Characterization of MdMADS2, a member of the SQUAMOSA subfamily of genes, in apple.

A MADS-box gene, MdMADS2, was isolated from the apple (Malus x domestica Borkh.) var Fuji and its developmental expression pattern was studied during flower development. MdMADS2 shares a high degree of amino acid sequence identity with the SQUAMOSA subfamily of genes. RNA blot analysis showed that MdMADS2 is transcribed through all stages of flower development, and its transcription was seen in the four floral organs. RNA in situ hybridization revealed that the MdMADS2 mRNA is expressed both in the inflorescence meristem and in the floral meristem. The MdMADS2 transcript was detected at all stages of flower development. Protein localization analysis showed that MdMADS2 protein was excluded from the stamen and carpel primordia, in which a considerable MdMADS2 mRNA signal was detected. This indicates that posttanscriptional regulation may be involved in the MdMADS2-mediated control of flower development. Transgenic tobacco expressing the MdMADS2 gene from the cauliflower mosaic virus 35S promoter showed early flowering and shorter bolts, but did not show any homeotic changes in the floral organs. These results suggest that MdMADS2 plays an important role during early stages of flower development.

Amino Acid Sequence↗
PubMed1999

Cloning and molecular analyses of a gibberellin 20-oxidase gene expressed specifically in developing seeds of watermelon.

To understand the biosynthesis and functional role of gibberellins (GAs) in developing seeds, we isolated Cv20ox, a cDNA clone from watermelon (Citrullus lanatus) that shows significant amino acid homology with GA 20-oxidases. The complementary DNA clone was expressed in Escherichia coli as a fusion protein, which oxidized GA(12) at C-20 to the C(19) compound GA(9), a precursor of bioactive GAs. RNA-blot analysis showed that the Cv20ox gene was expressed specifically in developing seeds. The gene was strongly expressed in the integument tissues, and it was also expressed weakly in inner seed tissues. In parthenocarpic fruits induced by 1-(2-chloro-4-pyridyl)-3-phenylurea treatment, the expression pattern of Cv20ox did not change, indicating that the GA 20-oxidase gene is expressed primarily in the maternal cells of developing seeds. The promoter of Cv20ox was isolated and fused to the beta-glucuronidase (GUS) gene. In a transient expression system, beta-glucuronidase staining was detectable only in the integument tissues of developing watermelon seeds.

5' Untranslated Regions↗
PubMed1999

Expression of the Escherichia coli catabolic threonine dehydratase in Corynebacterium glutamicum and its effect on isoleucine production.

The catabolic or biodegradative threonine dehydratase (E.C. 4.2.1. 16) of Escherichia coli is an isoleucine feedback-resistant enzyme that catalyzes the degradation of threonine to alpha-ketobutyrate, the first reaction of the isoleucine pathway. We cloned and expressed this enzyme in Corynebacterium glutamicum. We found that while the native threonine dehydratase of C. glutamicum was totally inhibited by 15 mM isoleucine, the heterologous catabolic threonine dehydratase expressed in the same strain was much less sensitive to isoleucine; i.e., it retained 60% of its original activity even in the presence of 200 mM isoleucine. To determine whether expressing the catabolic threonine dehydratase (encoded by the tdcB gene) provided any benefit for isoleucine production compared to the native enzyme (encoded by the ilvA gene), fermentations were performed with the wild-type strain, an ilvA-overexpressing strain, and a tdcB-expressing strain. By expressing the heterologous catabolic threonine dehydratase in C. glutamicum, we were able to increase the production of isoleucine 50-fold, whereas overexpression of the native threonine dehydratase resulted in only a fourfold increase in isoleucine production. Carbon balance data showed that when just one enzyme, the catabolic threonine dehydratase, was overexpressed, 70% of the carbon available for the lysine pathway was redirected into the isoleucine pathway.

Biomass↗
PubMed1998

Characterization of a tobacco MADS-box gene homologous to AGL2.

Flower development is regulated by a group of regulatory factors containing the MADS box domain. Recently, we isolated and characterized a tobacco MADS-box gene, NtMADS1, which is homologous to AGL2 in Arabidopsis. Sequence analysis revealed that NtMADS1 encodes a putative MADS-box protein homologous to the AGL2 with 68.4% identity and 82% similarity in amino acids. The NtMADS1 gene started to express at a very early stage of flower development, such as floral primodia, and the expression was maintained during the entire floral development. In the tobacco flower, the gene was expressed in all four floral organs, namely the sepal, petal, anther, and carpel, and was not detected in the vegetative organs such as the leaf and root. In situ hybridization was also performed to monitor the detailed expression pattern of NtMADS1 at the tissue level. These results indicate that NtMADS1 is the AGL2 homolog of tobacco and plays important roles in the floral development.

Amino Acid Sequence↗
PubMed1998

Expressed sequence tags of fruits, peels, and carpels and analysis of mRNA expression levels of the tagged cDNAs of fruits from the Fuji apple.

In order to understand molecular events during fruit development and provide genetic resources for molecular breeding, 430 expressed sequence tags (ESTs) were generated from randomly selected clones of cDNA libraries prepared from young fruits, peels of mature fruits, and carpels of the Fuji apple (Malus domestica Borkh.). Database comparisons of the ESTs revealed that 180 non-redundant clones showed a high similarity with previously identified genes. Among these, 138 clones exhibited a homology with previously identified plant genes and 12 were identical to genes that were previously identified from apples. The deduced amino acid sequences of 42 clones had a homology to proteins that have not been reported from plants. Eighteen cDNA clones from the young fruit library were selected for studying expression levels and patterns in reproductive organs and leaves. This study revealed that the clones can be classified into 3 different groups based on their expression levels. The first 9 clones were expressed strongly in at least one reproductive organ. Eight of these clones (vacuolar processing protease, sucrose phosphate synthase, arabinogalactan protein, UDP-glucose glucosyl transferase, major allergen D1, cystein proteinase inhibitor, lipoxygenase, and protease subunit SUG2) were highly expressed in mature flowers and young fruits, whereas one clone (z-carotene desaturase protein precursor) was preferentially expressed in mature flowers but weakly in young fruits. The second group includes 6 cDNA clones (glucose transport protein, aminomethyl transferase precursor protein, dTDP-D-glucose-4,6-dehydrogenase, 2 types of protein kinase, and selenium binding protein) that were weakly expressed. These clones were characterized by their preferential expression patterns in mature flowers and young fruits. The transcripts of 3 cDNA clones in the third group (vacuolar aminopetidase, beta-galactosidase, and EREBP-4) were detectable only by RT-PCR and they were preferentially expressed in young fruits. These results indicate that most ESTs that were isolated from young fruits are preferentially expressed in reproductive organs and thereby play important roles during reproductive organ development.

DNA, Complementary↗
PubMed1998

Expressed sequence tags of radish flower buds and characterization of a CONSTANS LIKE 1 gene.

Expressed sequence tag (EST) analysis was conducted for young flower buds of radish plants. Among a total of 66 ESTs examined, 40 showed a significant similarity to previously identified genes. Twenty-eight ESTs were similar to proteins identified in other plants, 11 were similar to eukaryotic proteins other than plants, and one was similar to a prokaryotic protein. Four clones were selected for further studies. EST clone 81, which showed a homology to germin-like proteins was expressed more abundantly in leaves and roots as compared to flower buds. Clone 105 was highly homologous to the translation inhibitor protein and was expressed in all three organs, but the expression level was higher in flower buds and roots. Another EST clone, 133, which shared a significant similarity with the Ran-binding protein, hybridized to two different size transcripts that were detectable only in flower buds. Clone 39 was a homolog of CONSTANS, which is a gene involved in controlling the flowering time in Arabidopsis. The cDNA clone of EST clone 39 containing the entire open reading frame was obtained and designated as RsCOL1 (Raphanus sativus CONSTANS LIKE 1). It was 1049 bp long and contained an open reading frame of 307 amino acid residues (calculated molecular mass = 33.1 kDa). The RsCOL1 protein contained two putative zinc finger motifs in the amino terminal region which were 59% identical to the corresponding region of the Arabidopsis CO protein. The radish protein also contained a predicted nuclear localization domain in the carboxyl terminal region which was 87% identical to the corresponding region of CO. DNA blot analysis revealed that the radish genome contained several genes similar to RsCOL1. RNA blot analysis showed that RsCOL1 was strongly expressed in flower buds at the early bolting stage, and the expression level declined as the flower bud matured. The transcript was also detectable in leaves and roots. In mature flowers, the RsCOL1 transcript was present primarily in carpels.

Amino Acid Sequence↗
PubMed1998

Secretion of biologically active human interleukin-2 and interleukin-4 from genetically modified tobacco cells in suspension culture.

Biologically active human interleukin-2 (IL-2) and IL-4, key lymphokines involved in immune regulation, were produced and secreted into the medium by genetically modified Nicotiana tabacum cells grown in suspension culture. Secretion through the plasma membrane and cell wall into the medium was facilitated by the natural mammalian leader sequences. IL-2 and IL-4 were detected in the medium at concentrations of 0.10 and 0.18 microgram/mL, respectively, although higher levels were detected within the lymphokine-producing cells (approximately 0.80 microgram/mL for IL-2 and approximately 0.28 microgram/mL for IL-4). By Western blot, IL-4 was found to be secreted as two small polypeptides with molecular masses of approximately 18-20 kDa. The biological activity of IL-2 was determined by cell proliferation of the IL-2-dependent murine CTLL-2 cell line, while that of IL-4 was determined by cell proliferation of the CTLL-2 cell line [CT.h4S] which was stably transfected with the human IL-4 receptor. These findings indicate that plant suspension culture can be used to produce and secrete into the medium a variety of biologically active mammalian proteins that are of clinical and diagnostic relevance.

Base Sequence↗
PubMed1998

A comparative study of the dose-response and time course of action of rocuronium and vecuronium in anesthetized adult patients.

STUDY OBJECTIVES: (1) To compare the dose-response relations of rocuronium and vecuronium in healthy adult patients anesthetized with nitrous oxide-oxygen-fentanyl-thiopental; and (2) to evaluate the time-course of action of two drugs following equipotent doses. DESIGN: Prospective, randomized, clinical comparison. SETTING: Operating room, Plastic Surgery Hospital of the Chinese Academy of Medical Sciences and Peking Union Medical College. PATIENTS: 60 ASA physical status I patients, aged 17-51 years, scheduled for elective plastic surgery. INTERVENTIONS: All patients were randomly assigned to either the rocuronium or vecuronium group. General anesthesia was induced with thiopental 4 to 6 mg/kg and fentanyl 2 to 4 micrograms/kg intravenously (i.v.), and maintained with 60% nitrous oxide (N2O) in oxygen. Further increments of thiopental or fentanyl were given as required. The dose-response relations of rocuronium and vecuronium were determined by the cumulative dose-response technique. MEASUREMENTS AND MAIN RESULTS: Neuromuscular function was assessed mechanomyographically with train-of-four (TOF) stimulation at the wrist every 12 seconds. The percentage depression of first twitch (T1) was used as the study parameter. The cumulative dose-response curve of vecuronium was shifted to the left in a parallel fashion compared with that of rocuronium. As assessed by linear regression, the potency ratio of vecuronium: rocuronium was 1:7.2. There were significant differences in the ED50, ED90, and ED95 between the two drugs. After i.v. administration of equipotent doses of both drugs (2 x ED90), the duration of peak effect, clinical duration, recovery index, and total duration were not significantly different between the two drugs. CONCLUSIONS: Compared with vecuronium, rocuronium is a low-potency, nondepolarizing relaxant, and its neuromuscular blocking potency is approximately 15% that of vecuronium in adult patients anesthetized with N2O and fentanyl. Following equipotent doses, the time-course of recovery for rocuronium is similar to that of vecuronium.

Adolescent↗
PubMed1998

Identification of class B and class C floral organ identity genes from rice plants.

The functions of two rice MADS-box genes were studied by the loss-of-function approach. The first gene, OsMADS4, shows a significant homology to members in the PISTILLATA (PI) family, which is required to specify petal and stamen identity. The second gene, OsMADS3, is highly homologous to the members in the AGAMOUS (AG) family that is essential for the normal development of the internal two whorls, the stamen and carpel, of the flower. These two rice MADS box cDNA clones were connected to the maize ubiquitin promoter in an antisense orientation and the fusion molecules were introduced to rice plants by the Agrobacterium-mediated transformation method. Transgenic plants expressing antisense OsMADS4 displayed alterations of the second and third whorls. The second-whorl lodicules, which are equivalent to the petals of dicot plants in grasses, were altered into palea/lemma-like organs, and the third whorl stamens were changed to carpel-like organs. Loss-of-function analysis of OsMADS3 showed alterations in the third and fourth whorls. In the third whorl, the filaments of the transgenic plants were changed into thick and fleshy bodies, similar to lodicules. Rather than making a carpel, the fourth whorl produced several abnormal flowers. These phenotypes are similar to those of the agamous and plena mutants in Arabidopsis and Antirrhinum, respectively. These results suggest that OsMADS4 belongs to the class B gene family and OsMADS3 belongs to the class C gene family of floral organ identity determination.

Cloning, Molecular↗
PubMed1998

Influence of acute normovolaemic haemodilution on the relation between the dose and response of rocuronium bromide.

The influence of acute moderate haemodilution on the relation between dose and response for rocuronium was evaluated in 60 adult patients, ASA grade I, undergoing elective plastic surgery. The patients were randomly allocated to either the control or the haemodilution group. Following the induction of general anaesthesia, the status of acute moderate haemodilution in the haemodilution group was achieved by draining venous blood, and intravenous infusion of lactated Ringer's solution, 6% dextran or gelofusine, during which the levels of haemoatocrit and haemoglobin dropped from 44% to 27.5% and from 148.3 to 91.3 g L-1, respectively. Neuromuscular function was assessed mechanomyographically with train-of-four stimulation at the wrist every 12 s and the percentage depression of T1 response was used as the study parameter. The relation between dose and response for rocuronium in the two groups was determined by the cumulative dose-response technique. The results showed that the dose-response curve for rocuronium during acute moderate haemodilution was shifted in a parallel fashion to the left and the potency of rocuronium was increased. There were significant differences in ED50, ED90 and ED95 between the two groups. The ED50, ED90 and ED95 of rocuronium in the haemodilution group was decreased by 28.2%, 35.4% and 38.8%, respectively, compared with the control group.

Adolescent↗