Dear Editor,Epstein-Barr virus(EBV,also termed human herpesvirus-4)was the first identified human tumor virus.Since its discovery in 1964,studies have shown that EBV infects over 90%of all people by the time they are ...Dear Editor,Epstein-Barr virus(EBV,also termed human herpesvirus-4)was the first identified human tumor virus.Since its discovery in 1964,studies have shown that EBV infects over 90%of all people by the time they are adults(Williams and Crawford 2006).EBV infection can result in mucocutaneous and systemic diseases,ranging from selflimited illnesses to aggressive malignancies,including B cell Hodgkin lymphoma and nasopharyngeal carcinoma.In vitro,EBV transforms resting B cells into proliferating blast cells(Pope et al.1968).展开更多
Senescence,a crucial developmental process in the life cycle of plants,involves programmed destruction of cellular components of leaves.The onset of senescence is synchronized with other developmental processes for su...Senescence,a crucial developmental process in the life cycle of plants,involves programmed destruction of cellular components of leaves.The onset of senescence is synchronized with other developmental processes for successful reproduction since senescence eventually leads to cell death.Arabinosyltransferase FASCIATED AND BRANCHED 2(FAB2)is known to control meristem proliferation.Here,we show that FAB2 could inhibit premature leaf senescence in tomato plants.Both chemically mutagenized and CRISPR-generated fab2 mutants exhibited excessively accelerated senescence,which resulted in sterility.Transcriptome analysis revealed that FAB2 extended leaf longevity by suppressing transcription of genes highly expressed in mature leaves.Transcription of FAB2 was increased in younger leaves,potentially inhibiting premature leaf senescence.The precocious senescence of fab2 mutants was in contrast to fasciated inflorescence(fin)mutants,which carried mutations in a hydroxyproline O-arabinosyltransferase gene,leading to meristem overproliferation.Our observations indicate that complex genetic hierarchy in the cascade of tomato arabinosyltransferases could control different aspects of developmental processes such as stem cell proliferation and senescence.展开更多
The heavy chain Fd genes and K chain genes of immunoglobulin were amplified by RT-PCR from PBL of three volunteer donors with HIV-positive. Phage antibody library was constructed with the Fd genes and K chain genes us...The heavy chain Fd genes and K chain genes of immunoglobulin were amplified by RT-PCR from PBL of three volunteer donors with HIV-positive. Phage antibody library was constructed with the Fd genes and K chain genes using pComb3 as vector. Three-round selection against coated gpl20 showed specific enrichment of phage antibodies. After the third round selection, 40 out of 50 clones exhibited gpl20 binding capacity. The specificity of the clones was verified by ELISA and competition inhibition ELISA. The V_H was derived from subgroups V_Ⅱ and V_Ⅲ, V_L belonged to subgroups V_K Ⅰ and V_K Ⅲ with DNA sequencing. These results suggest that the antibodies obtained are specific to gpi20.展开更多
基金supported by the National Natural Science Foundation of China (Grant Numbers: 81402542 and 81772166)the scholarship of Pujiang Talents in Shanghai to Fang Wei (Grant Number: 14PJ1405600)
文摘Dear Editor,Epstein-Barr virus(EBV,also termed human herpesvirus-4)was the first identified human tumor virus.Since its discovery in 1964,studies have shown that EBV infects over 90%of all people by the time they are adults(Williams and Crawford 2006).EBV infection can result in mucocutaneous and systemic diseases,ranging from selflimited illnesses to aggressive malignancies,including B cell Hodgkin lymphoma and nasopharyngeal carcinoma.In vitro,EBV transforms resting B cells into proliferating blast cells(Pope et al.1968).
基金funded by National Research Foundation(NRF)of the Ministry of Science and ICT(MSIT),Republic of Korea(Grant Nos.2022R1C1C1002941,2020R1A2C1004273,2020R1A2C1101915)。
文摘Senescence,a crucial developmental process in the life cycle of plants,involves programmed destruction of cellular components of leaves.The onset of senescence is synchronized with other developmental processes for successful reproduction since senescence eventually leads to cell death.Arabinosyltransferase FASCIATED AND BRANCHED 2(FAB2)is known to control meristem proliferation.Here,we show that FAB2 could inhibit premature leaf senescence in tomato plants.Both chemically mutagenized and CRISPR-generated fab2 mutants exhibited excessively accelerated senescence,which resulted in sterility.Transcriptome analysis revealed that FAB2 extended leaf longevity by suppressing transcription of genes highly expressed in mature leaves.Transcription of FAB2 was increased in younger leaves,potentially inhibiting premature leaf senescence.The precocious senescence of fab2 mutants was in contrast to fasciated inflorescence(fin)mutants,which carried mutations in a hydroxyproline O-arabinosyltransferase gene,leading to meristem overproliferation.Our observations indicate that complex genetic hierarchy in the cascade of tomato arabinosyltransferases could control different aspects of developmental processes such as stem cell proliferation and senescence.
文摘The heavy chain Fd genes and K chain genes of immunoglobulin were amplified by RT-PCR from PBL of three volunteer donors with HIV-positive. Phage antibody library was constructed with the Fd genes and K chain genes using pComb3 as vector. Three-round selection against coated gpl20 showed specific enrichment of phage antibodies. After the third round selection, 40 out of 50 clones exhibited gpl20 binding capacity. The specificity of the clones was verified by ELISA and competition inhibition ELISA. The V_H was derived from subgroups V_Ⅱ and V_Ⅲ, V_L belonged to subgroups V_K Ⅰ and V_K Ⅲ with DNA sequencing. These results suggest that the antibodies obtained are specific to gpi20.
