A novel nodulin gene, GmN479 genomic clone composing of 3 630 nucleotides was isolated from mature soybean nodules using GmN479 cDNA as a probe by subtractive hybridization procedure. GmN479 encodes 170 amino acids wi...A novel nodulin gene, GmN479 genomic clone composing of 3 630 nucleotides was isolated from mature soybean nodules using GmN479 cDNA as a probe by subtractive hybridization procedure. GmN479 encodes 170 amino acids with 2.09 kb nucleotides promoter region, and contains two important upstream promoter elements, one is a conserved cis-acting sequence motif 5′-AAAGAT-3′ controlling nodulin gene expression, and the other is typical CAAT boxes. GmN479 gene has a single zinc-finger C2H2 domain YSCAFCQRGFSNAQALLGGHMNIH and a conserved motif, QALGGHMN in the zinc-finger with a short leucine repeat in the LDLELRLGL motif closed to C-terminal. These two conserved motifs share respectively higher identity with those in the floral regulator SUPERMAN gene, indicating that GmN479 may function as a transcriptional regulator, and is a likely candidate for playing a role in nodule-morphogenesis. Blotting data showed that GmN479 is a single copy presenting in the genome of soybean nodule, and its expression profile is similar to that of Lb-a, but it is different from that of ENOD2. GUS staining showed that GmN479 promoter just functions in the infected cells of nodules, indicating that the GmN479 is one of the truly symbiotically induced host genes, and belongs to a late nodulin gene. The expression pattern of GmN479 gene seems to imply that it may be closely related to the development of the nodule. In a sense, it may be a useful marker for identifying the development of the infected cell system in the nodules of soybean.展开更多
Nodulin 26-like intrinsic proteins(NIPs) are a family of channel-forming transmembrane proteins that function in the transport of water and other small molecules.Some NIPs can mediate silicon transport across plasma m...Nodulin 26-like intrinsic proteins(NIPs) are a family of channel-forming transmembrane proteins that function in the transport of water and other small molecules.Some NIPs can mediate silicon transport across plasma membranes and lead to silicon accumulation in plants,which is beneficial for the growth and development of plants.Cucumber is one of the most widely consumed vegetables;however,the functions of NIPs in this crop are still largely unknown.Here,we report the functional characteristics of Cs NIP2;2.It was found that Cs NIP2;2 is a tandem repeat of Cs NIP2;1,which had been demonstrated to be a silicon influx transporter gene.Cs NIP2;2 has a selectivity filter composed of cysteine,serine,glycine and arginine(CSGR),which is different from all previously characterized silicon influx transporters in higher plants at the second helix position.Xenopus laevis oocytes injected with Cs NIP2;2 c RNA demonstrated a higher uptake of silicon than the control,and the uptake remained unchanged under low temperature.Cs NIP2;2 was found to be expressed in the root,stem,lamina and petiole,and exogenous silicon treatment decreased its expression in the stem but not in other tissues.Transient expression of Cs NIP2;2-e GFP fusion sequence in onion epidermal cells showed that Cs NIP2;2 was localized to the cell nucleus,plasma membrane and an unknown structure inside the cell.The results suggest that Cs NIP2;2 is a silicon influx transporter in cucumber,and its subcellular localization and the selectivity filter are different from those of the previously characterized silicon influx transporters in other plants.These findings may be helpful for understanding the functions of NIPs in cucumber plants.展开更多
For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y 18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter....For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y 18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter. These vectors were different only in promoter regions; three truncations of the nodulinlike promoter took the place of the CaMV35S promoter in the pBI 121 plant expression vector. Then, the three vectors were introduced into cotton plants via the pollen tube pathway. The expression patterns of the gus gene driven by nodulin-like promoter truncations were investigated in the offspring of transgenic cotton plants. Histochemical GUS staining and fluorescence quantitative analysis were performed to achieve this goal. The results showed that the nodulin-like promoter was a strong, highly reproductive organspecific promoter, which demonstrated a much higher driver activity than the CaMV35S promoter did in cotton reproductive organs, but relatively lower activity in vegetation. Identification of the speciality and strength-determining regions of the nodulin-like promoter was also undertaken.展开更多
基金supported by the National Key Project for Cultivation of New Varieties of Genetically Modified Organisms (2008ZX08002-005)
文摘A novel nodulin gene, GmN479 genomic clone composing of 3 630 nucleotides was isolated from mature soybean nodules using GmN479 cDNA as a probe by subtractive hybridization procedure. GmN479 encodes 170 amino acids with 2.09 kb nucleotides promoter region, and contains two important upstream promoter elements, one is a conserved cis-acting sequence motif 5′-AAAGAT-3′ controlling nodulin gene expression, and the other is typical CAAT boxes. GmN479 gene has a single zinc-finger C2H2 domain YSCAFCQRGFSNAQALLGGHMNIH and a conserved motif, QALGGHMN in the zinc-finger with a short leucine repeat in the LDLELRLGL motif closed to C-terminal. These two conserved motifs share respectively higher identity with those in the floral regulator SUPERMAN gene, indicating that GmN479 may function as a transcriptional regulator, and is a likely candidate for playing a role in nodule-morphogenesis. Blotting data showed that GmN479 is a single copy presenting in the genome of soybean nodule, and its expression profile is similar to that of Lb-a, but it is different from that of ENOD2. GUS staining showed that GmN479 promoter just functions in the infected cells of nodules, indicating that the GmN479 is one of the truly symbiotically induced host genes, and belongs to a late nodulin gene. The expression pattern of GmN479 gene seems to imply that it may be closely related to the development of the nodule. In a sense, it may be a useful marker for identifying the development of the infected cell system in the nodules of soybean.
基金supported by the National Key Research and Development Program of China (2018YFD1000800)the National Natural Science Foundation of China (32072561 and 31772290)。
文摘Nodulin 26-like intrinsic proteins(NIPs) are a family of channel-forming transmembrane proteins that function in the transport of water and other small molecules.Some NIPs can mediate silicon transport across plasma membranes and lead to silicon accumulation in plants,which is beneficial for the growth and development of plants.Cucumber is one of the most widely consumed vegetables;however,the functions of NIPs in this crop are still largely unknown.Here,we report the functional characteristics of Cs NIP2;2.It was found that Cs NIP2;2 is a tandem repeat of Cs NIP2;1,which had been demonstrated to be a silicon influx transporter gene.Cs NIP2;2 has a selectivity filter composed of cysteine,serine,glycine and arginine(CSGR),which is different from all previously characterized silicon influx transporters in higher plants at the second helix position.Xenopus laevis oocytes injected with Cs NIP2;2 c RNA demonstrated a higher uptake of silicon than the control,and the uptake remained unchanged under low temperature.Cs NIP2;2 was found to be expressed in the root,stem,lamina and petiole,and exogenous silicon treatment decreased its expression in the stem but not in other tissues.Transient expression of Cs NIP2;2-e GFP fusion sequence in onion epidermal cells showed that Cs NIP2;2 was localized to the cell nucleus,plasma membrane and an unknown structure inside the cell.The results suggest that Cs NIP2;2 is a silicon influx transporter in cucumber,and its subcellular localization and the selectivity filter are different from those of the previously characterized silicon influx transporters in other plants.These findings may be helpful for understanding the functions of NIPs in cucumber plants.
基金国家高技术研究发展计划(863计划)，the National Special Project for Cotton Development from Agricultural Department of the Chinese Government
文摘For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y 18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter. These vectors were different only in promoter regions; three truncations of the nodulinlike promoter took the place of the CaMV35S promoter in the pBI 121 plant expression vector. Then, the three vectors were introduced into cotton plants via the pollen tube pathway. The expression patterns of the gus gene driven by nodulin-like promoter truncations were investigated in the offspring of transgenic cotton plants. Histochemical GUS staining and fluorescence quantitative analysis were performed to achieve this goal. The results showed that the nodulin-like promoter was a strong, highly reproductive organspecific promoter, which demonstrated a much higher driver activity than the CaMV35S promoter did in cotton reproductive organs, but relatively lower activity in vegetation. Identification of the speciality and strength-determining regions of the nodulin-like promoter was also undertaken.
