Vernalization is an essential factor which affects the flowering development in cold_requiring plants. There is a key stage of nucleic acid and protein metabolism in the process of vernalization in winter wheat. To pr...Vernalization is an essential factor which affects the flowering development in cold_requiring plants. There is a key stage of nucleic acid and protein metabolism in the process of vernalization in winter wheat. To probe into the molecular determinants of vernalization , we examined mRNA populations in differently_treated plumules of winter wheat \%(Triticum aestivum \%L. \%cv\% Yanda 1817) using mRNA differential display. One vernalization_ related cDNA clone \%(VRC), VRC54\%, was identified and was only expressed at the key stage of 20 d vernalization, rather than at other stages of nonvernalization, 4 d vernalization and devernalization. Northern blot and sequence analysis indicated that \%VRC54\% was a novel vernalization_related clone found in higher plant which not only might play an important role in the floral induction in vernalization_requiring plants but also was different from the cold_acclimatized genes.展开更多
During the induction of gamete-producing gametangia, induced gametophytes werecollected at 4 days intervals (0,4,8, 12 d) and total RNAs were isolated by CsCl gradient ultracentrifu-gation. Some stage-specific express...During the induction of gamete-producing gametangia, induced gametophytes werecollected at 4 days intervals (0,4,8, 12 d) and total RNAs were isolated by CsCl gradient ultracentrifu-gation. Some stage-specific expressed mRNAs were identified by differential display of mRNAs from dif-ferent developing stages of the gametophytes. The cDNA of one specific mRNA was verified, cloned andsequenced. This gene was specifically expressed during 4 days of induction, and had partial homologoussequence with tobacco IAA-binding protein gene. It suggests that this cDNA may represent a gene whichis related to the LAA regulating function during the development of the gametophytes.展开更多
TDF1(transcription-drived fragment) was homologous to the predicted S. lycopersicum nonspecific lipid-transfer protein,nsLTP 2-like(91%), and it was significantly upregulated in response to C. fulvum(cladosporium fulv...TDF1(transcription-drived fragment) was homologous to the predicted S. lycopersicum nonspecific lipid-transfer protein,nsLTP 2-like(91%), and it was significantly upregulated in response to C. fulvum(cladosporium fulvum) infection in tomato plants.In this experiment, the full-length cDNA of nsLTP 2-like was cloned using RACE technology based on the sequence of TDF1(GenBank: JZ717725). A full-length, 625 bp(GenBank: KU366289), cDNA sequence, which with 98% similarity to nsLTP 2-like gene(GenBank: XM015233692) was obtained. This cDNA contains an ORF(open reading frame) with full-length of 345 bp, coding of 114 amino acids, including 12.3% Ala and Gly. Protein molecular weight was 11.51 ku, the isoelectric point(pI) was 8.99, and average overall hydrophilicity was 0.412, with one phosphorylation sites, belonging to volatile acidic nuclear protein. Secondary structure prediction showed that α-Helix accounts for 30.7%, extension chain for 12.28%, β-corner for 9.65%, and random coil for 47.37%. Through comparative analysis of the homology among species, it was found that the amino acid sequence of tomato nsLTP 2-like protein had a high similarity with other plants, and with a specific conserved sequence which might related features in nsLTP 2-like protein. It also be analyzed the gene expression pattern of tomato in different parts and under different stress conditions.The results showed that nsLTP 2-like gene was up-regulated in varying degrees, under the condition of cold stress, exogenous hormone spraying and cladosporium fulvum infection. Therefore, it was speculated that the gene played a role in response to abiotic and biotic stress in tomato.展开更多
A technique was developed for detecting venom phospholipase A2(PLA2) using serum and red blood cells. M1 and M2, two PLA2s isolated from Crotalus m.molossus (Northern black-tail rattlesnake), were used for preliminary...A technique was developed for detecting venom phospholipase A2(PLA2) using serum and red blood cells. M1 and M2, two PLA2s isolated from Crotalus m.molossus (Northern black-tail rattlesnake), were used for preliminary development of the as say. Various combinations of human, sheep, rat, and mouse red blood cells (RBC) with human,rat,and mouse sera were tested on their effectiveness to detect PLA2.Complete hemolysis (b hemolysis) was evident in the plate with rat RBC mixed with mouse serum.No hemolysis was detected in plates containing human RBC and human serum. Human RBC mixed with mouse serum proved to be ideal, even though this combination displayed incomplete hemolysis(a hemolysis).Susceptible RBC, in conjunction with rat or mouse serum, are excellent indicators for the presence of PLA2.Mixtures of RBC and serum in combination with BB4(E. coli) cells,λbacteriophage,and IPTG on LB agar plates provide an excellent detection system for cDNA clones that express venonl PLA2. Hemolysis surrounding a plaque is identified as positive for PLA2.展开更多
A synthetic polypeptide, pt27, which is encoded by a cDNA clone with antloncogene activity, p14-6, is found to be able to reduce remarkably the soft agar colony formation ability of part of DT cells and to raise their...A synthetic polypeptide, pt27, which is encoded by a cDNA clone with antloncogene activity, p14-6, is found to be able to reduce remarkably the soft agar colony formation ability of part of DT cells and to raise their resistance to the ouabaln toxtcity. This shows that the pt27 peptide can affect the DT cells In a manner similar to the p14- 6 done and provides evidence that the reverting action of the p14-6 to DT cells may be exerted by the expression of its cDNA.展开更多
The differential hybridization technique hasbeen widely used to identify genes that are dif-ferentially expressed.However,this approachhas several drawbacks.First,the screeningprocedures are rather labor-intensive and...The differential hybridization technique hasbeen widely used to identify genes that are dif-ferentially expressed.However,this approachhas several drawbacks.First,the screeningprocedures are rather labor-intensive and time-consuming.Second,the amount of phageDNAs transferred onto the two filters may notbe equivalent,which leads to an inaccurate se-lection of a positive clone.Third,isolation ofphage DNA is slow and cumbersome.Here,aPCR based differential screening method that展开更多
文摘Vernalization is an essential factor which affects the flowering development in cold_requiring plants. There is a key stage of nucleic acid and protein metabolism in the process of vernalization in winter wheat. To probe into the molecular determinants of vernalization , we examined mRNA populations in differently_treated plumules of winter wheat \%(Triticum aestivum \%L. \%cv\% Yanda 1817) using mRNA differential display. One vernalization_ related cDNA clone \%(VRC), VRC54\%, was identified and was only expressed at the key stage of 20 d vernalization, rather than at other stages of nonvernalization, 4 d vernalization and devernalization. Northern blot and sequence analysis indicated that \%VRC54\% was a novel vernalization_related clone found in higher plant which not only might play an important role in the floral induction in vernalization_requiring plants but also was different from the cold_acclimatized genes.
文摘During the induction of gamete-producing gametangia, induced gametophytes werecollected at 4 days intervals (0,4,8, 12 d) and total RNAs were isolated by CsCl gradient ultracentrifu-gation. Some stage-specific expressed mRNAs were identified by differential display of mRNAs from dif-ferent developing stages of the gametophytes. The cDNA of one specific mRNA was verified, cloned andsequenced. This gene was specifically expressed during 4 days of induction, and had partial homologoussequence with tobacco IAA-binding protein gene. It suggests that this cDNA may represent a gene whichis related to the LAA regulating function during the development of the gametophytes.
基金Supported by the National Key R&D Program of China(2017YFD0101900)China Agriculture Research System(CARS-23-A-16)the Science Foundation of Heilongjiang Province(C2017024)
文摘TDF1(transcription-drived fragment) was homologous to the predicted S. lycopersicum nonspecific lipid-transfer protein,nsLTP 2-like(91%), and it was significantly upregulated in response to C. fulvum(cladosporium fulvum) infection in tomato plants.In this experiment, the full-length cDNA of nsLTP 2-like was cloned using RACE technology based on the sequence of TDF1(GenBank: JZ717725). A full-length, 625 bp(GenBank: KU366289), cDNA sequence, which with 98% similarity to nsLTP 2-like gene(GenBank: XM015233692) was obtained. This cDNA contains an ORF(open reading frame) with full-length of 345 bp, coding of 114 amino acids, including 12.3% Ala and Gly. Protein molecular weight was 11.51 ku, the isoelectric point(pI) was 8.99, and average overall hydrophilicity was 0.412, with one phosphorylation sites, belonging to volatile acidic nuclear protein. Secondary structure prediction showed that α-Helix accounts for 30.7%, extension chain for 12.28%, β-corner for 9.65%, and random coil for 47.37%. Through comparative analysis of the homology among species, it was found that the amino acid sequence of tomato nsLTP 2-like protein had a high similarity with other plants, and with a specific conserved sequence which might related features in nsLTP 2-like protein. It also be analyzed the gene expression pattern of tomato in different parts and under different stress conditions.The results showed that nsLTP 2-like gene was up-regulated in varying degrees, under the condition of cold stress, exogenous hormone spraying and cladosporium fulvum infection. Therefore, it was speculated that the gene played a role in response to abiotic and biotic stress in tomato.
文摘A technique was developed for detecting venom phospholipase A2(PLA2) using serum and red blood cells. M1 and M2, two PLA2s isolated from Crotalus m.molossus (Northern black-tail rattlesnake), were used for preliminary development of the as say. Various combinations of human, sheep, rat, and mouse red blood cells (RBC) with human,rat,and mouse sera were tested on their effectiveness to detect PLA2.Complete hemolysis (b hemolysis) was evident in the plate with rat RBC mixed with mouse serum.No hemolysis was detected in plates containing human RBC and human serum. Human RBC mixed with mouse serum proved to be ideal, even though this combination displayed incomplete hemolysis(a hemolysis).Susceptible RBC, in conjunction with rat or mouse serum, are excellent indicators for the presence of PLA2.Mixtures of RBC and serum in combination with BB4(E. coli) cells,λbacteriophage,and IPTG on LB agar plates provide an excellent detection system for cDNA clones that express venonl PLA2. Hemolysis surrounding a plaque is identified as positive for PLA2.
文摘A synthetic polypeptide, pt27, which is encoded by a cDNA clone with antloncogene activity, p14-6, is found to be able to reduce remarkably the soft agar colony formation ability of part of DT cells and to raise their resistance to the ouabaln toxtcity. This shows that the pt27 peptide can affect the DT cells In a manner similar to the p14- 6 done and provides evidence that the reverting action of the p14-6 to DT cells may be exerted by the expression of its cDNA.
文摘The differential hybridization technique hasbeen widely used to identify genes that are dif-ferentially expressed.However,this approachhas several drawbacks.First,the screeningprocedures are rather labor-intensive and time-consuming.Second,the amount of phageDNAs transferred onto the two filters may notbe equivalent,which leads to an inaccurate se-lection of a positive clone.Third,isolation ofphage DNA is slow and cumbersome.Here,aPCR based differential screening method that
