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1.
cDNA cloning and differential gene expression of three catalases in pumpkin   总被引:5,自引:0,他引:5  
Three cDNA clones (cat1, cat2, cat3) for catalase (EC 1.11.1.6) were isolated from a cDNA library of pumpkin (Cucurbita sp.) cotyledons. In northern blotting using the cDNA-specific probe, the cat1 mRNA levels were high in seeds and early seedlings of pumpkin. The expression pattern of cat1 was similar to that of malate synthase, a characteristic enzyme of glyoxysomes. These data suggest that cat1 might encode a catalase associated with glyoxysomal functions. Furthermore, immunocytochemical analysis using cat1-specific anti-peptide antibody directly showed that cat1 encoding catalase is located in glyoxysomes. The cat2 mRNA was present at high levels in green cotyledons, mature leaf, stem and green hypocotyl of light-grown pumpkin plant, and correlated with chlorophyll content in the tissues. The tissue-specific expression of cat2 had a strong resemblance to that of glycolate oxidase, a characteristic enzyme of leaf peroxisomes. During germination of pumpkin seeds, cat2 mRNA levels increased in response to light, although the increase in cat2 mRNA by light was less than that of glycolate oxidase. cat3 mRNA was abundant in green cotyledons, etiolated cotyledons, green hypocotyl and root, but not in young leaf. cat3 mRNA expression was not dependent on light, but was constitutive in mature tissues. Interestingly, cat1 mRNA levels increased during senescence of pumpkin cotyledons, whereas cat2 and cat3 mRNAs disappeared during senescence, suggesting that cat1 encoding catalase may be involved in the senescence process. Thus, in pumpkin, three catalase genes are differentially regulated and may exhibit different functions.  相似文献   

2.
Somatic cells from a first-generation red fluorescence protein transgenic cat (first RFP TG cat) were used to produce a recloned RFP transgenic cat (Re-RFP TG cat) (Felis catus) that systemically expressed RFP. A total of 281 RFP cloned embryos were transferred into 13 surrogate mothers (mean = 21 ± 7.7 embryos/recipient). One surrogate cat was diagnosed pregnant (7.7%) and delivered one live kitten. The presence of the RFP gene in the mRNA and genomic DNA of the Re-RFP TG cat was confirmed by polymerase chain reaction analyses, and red fluorescence was detected in its internal organs and placental tissue samples. Analysis of nine feline-specific microsatellite loci confirmed that the Re-RFP TG cat was genetically identical to the donor cat. To test whether results such as normality of offspring and a low cloning success were due to epigenetic modifications, global methylation of placenta from the two first cloned RFP TG cats (77.08% and 82.29%) and the Re-RFP TG cat (76.38%) were compared by bisulfite mutagenesis sequencing analysis. In conclusion, although cloning efficiency was low, we demonstrated the successful use of a cloned first RFP TG cat as a donor cat to produce a Re-RFP TG cat. These results may facilitate future developments in biomedical models for human therapeutic applications.  相似文献   

3.
Saccharomyces cerevisiae regulatory genes CAT1 and CAT3 constitute a positive control circuit necessary for derepression of gluconeogenic and disaccharide-utilizing enzymes. Mutations within these genes are epistatic to hxk2 and hex2, which cause defects in glucose repression. cat1 and cat3 mutants are unable to grow in the presence of nonfermentable carbon sources or maltose. Stable gene disruptions were constructed inside these genes, and the resulting growth deficiencies were used for selecting epistatic mutations. The revertants obtained were tested for glucose repression, and those showing altered regulatory properties were further investigated. Most revertants belonged to a single complementation group called cat4. This recessive mutation caused a defect in glucose repression of invertase, maltase, and iso-1-cytochrome c. Additionally, hexokinase activity was increased. Gluconeogenic enzymes are still normally repressible in cat4 mutants. The occurrence of recombination of cat1::HIS3 and cat3::LEU2 with some cat4 alleles allowed significant growth in the presence of ethanol, which could be attributed to a partial derepression of gluconeogenic enzymes. The cat4 complementation group was tested for allelism with hxk2, hex2, cat80, cid1, cyc8, and tup1 mutations, which were previously described as affecting glucose repression. Allelism tests and tetrad analysis clearly proved that the cat4 complementation group is a new class of mutant alleles affecting carbon source-dependent gene expression.  相似文献   

4.
Winger JA  Marletta MA 《Biochemistry》2005,44(10):4083-4090
The catalytic domains (alpha(cat) and beta(cat)) of alpha1beta1 soluble guanylate cyclase (sGC) were expressed in Escherichia coli and purified to homogeneity. alpha(cat), beta(cat), and the alpha(cat)beta(cat) heterodimeric complex were characterized by analytical gel filtration and circular dichroism spectroscopy, and activity was assessed in the absence and presence of two different N-terminal regulatory heme-binding domain constructs. Alpha(cat) and beta(cat) were inactive separately, but together the domains exhibited guanylate cyclase activity. Analysis by gel filtration chromatography demonstrated that each of the approximately 25-kDa domains form homodimers. Heterodimers were formed when alpha(cat) and beta(cat) were combined. Results from circular dichroism spectroscopy indicated that no major structural changes occur upon heterodimer formation. Like the full-length enzyme, the alpha(cat)beta(cat) complex was more active in the presence of Mn(2+) as compared to the physiological cofactor Mg(2+), although the magnitude of the difference was much larger for the catalytic domains than for the full-length enzyme. The K(M) for Mn(2+)-GTP was measured to be 85 +/- 18 microM, and in the presence of Mn(2+)-GTP, the K(D) for the alpha(cat)beta(cat) complex was 450 +/- 70 nM. The N-terminal heme-bound regulatory domain of the beta1 subunit of sGC inhibited the activity of the alpha(cat)beta(cat) complex in trans, suggesting a domain-scale mechanism of regulation by NO. A model in which binding of NO to sGC causes relief of an autoinhibitory interaction between the regulatory heme-binding domain and the catalytic domains of sGC is proposed.  相似文献   

5.
6.
The ability of domestic cat or leopard cat spermatozoa to penetrate zonae pellucidae (ZP) of salt-stored, domestic cat oocytes was examined as an assay for sperm capacitation. Ovarian oocytes were recovered after ovariectomy and matured in vitro for 18-36 h. Following removal of cumulus cells, the oocytes were used fresh, or stored (4 degrees C, 0.5-24 weeks) in a HEPES-buffered hypertonic salt solution. Electroejaculated, washed sperm (2-4 x 10(6) sperm/ml) were preincubated for 1.0 h (38 degrees C, 5% CO2 in air) and then co-incubated (2 x 10(5) sperm/ml) with fresh or stored oocytes for 6.0 h. Gametes were incubated in a protein-free, modified Tyrode's solution (TLP-PVA) or in the same medium containing 4.0 mg/ml bovine serum albumin (BSA; TALP-PVA). Treatments were compared for percentage ZP penetration (defined as sperm heads reaching more than halfway through the ZP) as an index of sperm capacitation. In both the domestic cat and leopard cat, there was no difference (P greater than 0.05) in sperm penetration of fresh ZP (domestic cat, 42.5 +/- 5.4%; leopard cat, 38.6 +/- 2.8%) or stored ZP (domestic cat, 32.4 +/- 4.2%; leopard cat, 27.6 +/- 2.3%). Sperm incubated in protein-free medium (TLP-PVA) were less capable (P less than 0.05) of ZP penetration (domestic cat, 14.6 +/- 5.9%; leopard cat, 7.9 +/- 3.0%) than sperm incubated in medium TALP-PVA containing BSA (domestic cat, 60.3 +/- 5.9%; leopard cat, 58.4 +/- 3.0%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Our study evaluated the effects on the prefrontal cortex, especially the inferior frontal gyrus (IFG), of people when touching and stroking a real or soft toy cat, using functional near infrared spectroscopy. Thirty under-graduate students (10 males, 20 females) were recruited and performed three tactile tasks with a real cat and a soft toy cat using their right hand. They also filled in the Self-Assessment Manikin (SAM), to measure their emotional responses, and the NEO-Five Factor Inventory, to assess their personalities. During the tactile interactions with the real cat, the integral values of oxygenated hemoglobin in the left IFG of the females were significantly greater than in the males. The valence scores of the SAM after the real cat-associated tasks in females were significantly higher than after the toy cat-associated tasks. Additionally, the number of times the females stroked the real cat was significantly positively correlated with the activation levels of the left IFG and the valence scores of the SAM. The activation levels of the left IFG in females were also positively correlated with neuroticism when stroking the real cat. Thus, in females, especially those with higher levels of neuroticism, touching/stroking the cat improved their mood. The effects of interacting with a cat may be different between the genders.  相似文献   

8.
The leopard cat (Prionailurus bengalensis), a member of the felidae family, is a threatened animal in South Korea. In terms of protecting endangered felids, nuclear transfer (NT) is a potentially valuable technique for assuring the continuation of species with dwindling numbers. In the present experiment, nuclear and microtubule remodeling and the in vitro developmental potential of enucleated domestic cat oocytes reconstructed with nuclei of somatic cells from either domestic cat fibroblast (DCF) or leopard cat fibroblast (LCF) were evaluated. Microtubule aster is allocated to de-condensed chromatin following nuclear transfer (3h after activation) of fibroblast cells from both domestic and leopard cats, suggesting the introduction of a somatic cell centrosome. The transferred fibroblast nuclei formed a large, swollen, pronuclear-like structure in most reconstructed oocytes, in the cat or leopard cat. At 18h following nuclear transfer, mitosis occurred, and according to the photo (F) it appears that spindle microtubules and two asters were observed. The percentages of blastocyst formation from nuclear transfer embryos derived from domestic cat fibroblasts (4/46, 8.6%) were not significantly different than those for nuclear transfer embryos constructed with leopard cat fibroblasts (4/52, 7.6%). These results indicate that nuclear and microtubule remodeling processes and in vitro developmental ability are similar in reconstructed cat oocytes following transfer of nuclei from either domestic or leopard cats.  相似文献   

9.
In the present study, we sought to elucidate the contribution of the Cryptococcus neoformans catalase gene family to antioxidant defense. We employed bioinformatics techniques to identify four members of the C. neoformans catalase gene family and created mutants lacking single or multiple catalase genes. Based on a phylogenetic analysis, CAT1 and CAT3 encode putative spore-specific catalases, CAT2 encodes a putative peroxisomal catalase, and CAT4 encodes a putative cytosolic catalase. Only Cat1 exhibited detectable biochemical activity in vitro, and Cat1 activity was constitutive in the yeast form of this organism. Although they were predicted to be important in spores, neither CAT1 nor CAT3 was essential for mating or spore viability. Consistent with previous studies of Saccharomyces cerevisiae, the single (cat1, cat2, cat3, and cat4) and quadruple (cat1 cat2 cat3 cat4) catalase mutant strains exhibited no oxidative-stress phenotypes under conditions in which either exogenous or endogenous levels of reactive oxygen species were elevated. In addition, there were no significant differences in the mean times to mortality between groups of mice infected with C. neoformans catalase mutant strains (the cat1 and cat1 cat2 cat3 cat4 mutants) and those infected with wild-type strain H99. We conclude from the results of this study that C. neoformans possesses a robust antioxidant system, composed of functionally overlapping and compensatory components that provide protection against endogenous and exogenous oxidative stresses.  相似文献   

10.
The ultrastructure of spermatozoa from the domestic tom cat and the Siberian tiger was studied. Semen was collected from anesthetized tom cats and Siberian tigers by electroejaculation. Spermatozoa were fixed and processed for examination by transmission electron microscopy. The principle differences between the spermatozoa from the two species were the head shape, mitochondrial organization in the neck area and structure of the fibrous sheath. Tom cat spermatozoa had an elongated oval-shaped head, while tiger spermatozoa had a more rounded head shape. Circularly oriented mitochondria in the neck area, near the proximal centriole, were frequently observed in tiger cells but rarely observed in tom cat cells. The semicircular ribs of tom cat spermatozoa were larger than the ribs of tiger spermatozoa. Also, the dense fibers (Numbers 3 and 8) of the corresponding microtubule doublets were fused or connected to the longitudinal columns in tiger spermatozoa but showed only occasional attachment in tom cat spermatozoa. These differences could influence results when the tom cat is used as a model for studying tiger semen.  相似文献   

11.
We conducted surveys of mutant allele frequencies of four cat populations in Arkansas and Tennessee during 2002. Our calculations and analyses support that Southwestern cat populations were relatively more genetically similar to each other than compared to cat populations in other areas of North America. However, the cat population of Fort Smith is slightly different from the other cat populations studied in the Southwestern United States. Although there is a clear significant spatial geographic pattern for many mutant coat allele frequencies in the United States and Canada cat populations (d, l, S, and W), our results revealed that there is not a significant isolation-by-distance model affecting these cat populations. Our data also support the historical migration hypothesis because our calculated allele frequencies were genetically similar to cat populations located in ancestral areas of Europe. Different phenograms, including new European cat genetic profiles, showed that the Southwestern cat populations studied are of a clear British origin. Therefore, migration routes of early Arkansas and Tennessee settlers help explain the similarities of allele frequencies among domestic cat populations.  相似文献   

12.
Following the curative resection of a pancreatic gastrinoma in a cat, gastrin peptides were purified from the tissue and sequenced. The sequence of cat gastrinoma G17 (18-34) confirms the previously published sequence. The sequence of cat G34 (1-34) is reported for the first time. The NH2-terminal portion of cat G34 differs from that of dog by having a Q (Gln) for L (Leu) at position 10 from the NH2-terminus.  相似文献   

13.
Summary Interspecies intracytoplasmic sperm injection has been carried out to understand species-specific differences in oocyte environments and sperm components during fertilization. While sperm aster organization during cat fertilization requires a paternally derived centriole, mouse and hamster fertilization occur within the maternal centrosomal components. To address the questions of where sperm aster assembly occurs and whether complete fertilization is achieved in cat oocytes by interspecies sperm, we studied the fertilization processes of cat oocytes following the injection of cat, mouse, or hamster sperm. Male and female pronuclear formations were not different in the cat oocytes at 6 h following cat, mouse or hamster sperm injection. Microtubule asters were seen in all oocytes following intracytoplasmic injection of cat, mouse or hamster sperm. Immunocytochemical staining with a histone H3-m2K9 antibody revealed that mouse sperm chromatin is incorporated normally with cat egg chromatin, and that the cat eggs fertilized with mouse sperm enter metaphase and become normal 2-cell stage embryos. These results suggest that sperm aster formation is maternally dependent, and that fertilization processes and cleavage occur in a non-species specific manner in cat oocytes.  相似文献   

14.
The behaviour of a group of female domestic cats (n = 10) under laboratory conditions is described. Behavioural observations were made on a total of 20 days during a 3-month period; only frequencies were recorded. Analysis of the winner/loser matrix revealed a linear rank order. This rank order correlated with several variables. The higher the rank, the more offensive threats a cat emitted overall, and the more defensive threats it received overall; within a pair, the higher-ranking cat displayed more offensive threats, whereas the lower-ranking cat displayed more defensive threats. The higher a rank, the more bouts of social licking a cat emitted overall, and the more bouts of social sniffing and social rubbing it received overall; within a pair, the higher-ranking cat tended to show more social licking, whereas the lower-ranking cat showed more social sniffing. The higher the rank, the more time a cat tended to spend on the floor, and the less time it spent in a 16-compartment complex; the further animals were apart in rank, the smaller were the proximity scores between them. Finally, higher-ranking cats tended to gain weight, whereas lower-ranking cats tended to lose weight. These data suggest that the concept of dominance may be applied to this group of cats. It is discussed whether the observed rank order is specific for indoor conditions under which the cats were living. The role of social licking is also discussed.  相似文献   

15.
Translocation of mtDNA into the nuclear genome, also referred to as numt, was first reported in the domestic cat (Felis catus) by Lopez et al. (1994). The Lopez-numt consisted of a translocation of 7.9 kbp of mtDNA that inserted into the domestic cat chromosome D2 around 1.8 million years ago. More than a decade later, the release of the domestic cat whole-genome shotgun sequences (1.9x coverage) provides the resource to obtain more comprehensive insight into the extent of mtDNA transfer over time in the domestic cat genome. MegaBLAST searches revealed that the cat genome harbors a wide variety of numts (298 320 bp), one-third of which likely correspond to the Lopez-numt tandem repeat, whereas the remaining numts are probably derived from multiple independent insertions, which in some cases were followed by segmental duplication after insertion in the nucleus. Numts were detected across most cat chromosomes, but the number of numts assigned to chromosomes is underestimated due to the relatively high number of numt sequences with insufficient flanking sequence to map. The catalog of cat numts provides a valuable resource for future studies in Felidae species, including its use as a tool to avoid numt contaminations that may confound population genetics and phylogenetic studies.  相似文献   

16.
《Anthrozo?s》2013,26(1):30-42
Abstract

Ninety-two cat owners, and 70 non-pet subjects were surveyed to determine the relationship between psychological health and pet ownership. The survey employed measures of general psychological health, depression, state and trait anxiety, sleep disturbance, nurturance, attitudes toward pets, social desirability, and a life events inventory. The study hypothesized that cat owners would be more psychologically healthy than non-pet owners and that this difference would be reflected in the cat owners having lower scores on the measures of general psychological health, depression, anxiety, and sleep disturbance. The study also proposed that cat owners would be more nurturing and have a more favorable attitude toward pets than non-pet owners. Findings showed that the cat owners had significantly lower scores for general psychological health, indicating a lower level of psychiatric disturbance, and could be considered to have better psychological health than the non-pet subjects. The cat owners also had significantly higher pet attitude scores than non-pet subjects, indicating a more favorable attitude toward pets. No significant differences were found for depression, anxiety, sleep disturbance, nurturance, social desirability, or life events for cat owners and non-pet subjects.  相似文献   

17.
Synopsis Sections of ovary from plains viscacha, cat, ferret, rabbit, rat, guinea-pig and roe deer have been histochemically processed to demonstrate acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in nervous and non-nervous tissue. The effects of different reproductive states on enzyme activity were observed in some animals. AChE-containing nerves were sparse in rabbit and rat but plentiful in cat and roe deer. Nerves containing BuChE were not detectable in ferret or guinea-pig and were rare in cat. Species variations in the activity and type of enzyme were also found in non-neuronal tissues. Some blood vessels in the ovaries of guinea-pig and viscacha contained AChE. No other species showed a reaction for AChE in non-neuronal stromal tissue but BuChE was present at this site in all animals except rat. Granulosa cells reacted for AChE only in cat and rabbit while luteal cells were reactive in cat, rabbit and roe deer. Some BuChE activity was present in granulosa and or luteal cells in all species except roe deer. In rat, BuChE activity in luteal cells increased during oregnaney and the early phase of pseudopregnancy. The difficulty of assigning a function to ovarian cholinesterases is discussed.  相似文献   

18.
Activation of an enhancerless gene by chromosomal integration.   总被引:6,自引:3,他引:3       下载免费PDF全文
Expression of enhancerless (E-) and enhancer-containing (E+) genes that are chromosomally integrated was examined. An E- plasmid (pE-cat) containing a chloramphenicol acetyltransferase (cat) gene linked to the simian virus 40 (SV40) early promoter or its E+ counterpart plasmid (pE+-cat) containing the SV40 enhancer was cotransfected into thymidine kinase (TK)-deficient L cells with a cloned tk gene. A number of TK+ transformants were isolated, and expression of the cointegrated cat gene in these cell lines was quantitatively determined by the assay of CAT activity. The results indicated unexpectedly that the E- cat gene was as actively expressed as the E+ cat gene. Analysis of CAT mRNA by primer extension indicated that the E- cat gene, as well as the E+ cat gene, was transcribed from the "native" initiation site contained in the SV40 early promoter region. The active expression of the E- cat gene was maintained in secondary TK+ transformants that arose by transfection with genomic DNA from the primary transformant. These results suggest that expression of the integrated E- cat gene is activated by endogenous enhancer elements.  相似文献   

19.
Feral cat control using aerial broadcasting of toxic baits continues to be used in the rangelands of Western Australia. The effectiveness of these operations has sometimes been compromised by different environmental factors that affect prey and cat numbers. This study demonstrates that the ratio of cats to their preferred prey (small mammals) can be used to predict the most effective time to bait. The regular baiting of three conservation sites offered an opportunity to study the relationship between feral cat abundance, the abundance of their prey and ingestion of toxic baits. Peron Peninsula on the mid‐west coast, Lorna Glen station in the northern Goldfields and the central Gibson Desert of Western Australia are sites where cat control using toxic baits has been routinely applied over the last 15 years. We postulated that bait ingestion by cats was linked to the availability of live prey. Small mammal abundance (capture rates in pit‐fall traps) and relative cat abundance (based on daily track counts) were assessed at these sites and the data used to produce a predator‐prey ratio index (PPRI). We used generalised linear mixed models to test the effect of prey abundance, prebaiting cat abundance and PPRI on baiting efficacy (BE). The best model for predicting efficacy of baiting contained only PPRI. This simple model was able to predict baiting success over the entire range of outcomes, from highly successful ( >75% cat reduction) to unsuccessful (0% cat reduction). The ability to predict feral cat BE in advance of planned toxic baiting operations will provide a valuable tool for wildlife managers involved in cat control.  相似文献   

20.
Embryo technology in conservation efforts for endangered felids   总被引:7,自引:0,他引:7  
Pope CE 《Theriogenology》2000,53(1):163-174
Most of the 36 species of wild cats are classified as threatened, vulnerable or endangered due to poaching and habitat loss. The important role of assisted reproduction techniques (ART) as part of a multifaceted captive breeding program for selected wild cat species is gradually gaining acceptance. This recognition is a result of the progress made during the last decade in which the feasibility of oocyte recovery from gonadotropin-treated females, in vitro fertilization, embryo cryopreservation and embryo transfer (ET) was demonstrated in the domestic cat (Felis catus). Additionally, embryos have been produced in vitro from oocytes matured in vitro after recovery from ex situ ovaries of both domestic and non-domestic cat species and domestic kittens have been born following transfer of these embryos. In vitro fertilization has been successful in at least one-third of wild cat species and kittens were born after transfer of Indian desert cat (Felis sylvestris ornata) embryos into a domestic cat and con-specific transfer of tiger (Panthera tigris) embryos. The domestic cat is not only a valuable model for development of in vitro techniques but may serve as a recipient of embryos from several species of small wild cats.  相似文献   

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