MicroRNAs （miRNAs） are endogenous -22 nucleotide noncoding RNAs that regulate the expression of complementary messenger RNAs （mRNAs）. Thousands of miRNA genes have been found in diverse species, and many of them a...MicroRNAs （miRNAs） are endogenous -22 nucleotide noncoding RNAs that regulate the expression of complementary messenger RNAs （mRNAs）. Thousands of miRNA genes have been found in diverse species, and many of them are highly conserved. With the miRNA roles identified in nearly all aspects of biological processes, evidence is mounting that miRNAs could represent a new layer of regulatory network, and their regulatory effect might be much more pervasive than previously suspected. Here we focus on the posttranscriptional level gene regulation of miRNAs in animals and review how the miRNAs act to sustain and shape up the expression profiles of specific cell types; how the miRNAs integrate into the existing gene regulatory networks; and how the miRNAs influence the evolution of 3＇UTR of mammalian mRNAs.展开更多
Leptinotarsa decemlineata adults exhibit a season-dependent activity. In spring, post-diapause beetles often fly a long distance from overwintering sites to potato fields. In summer and autumn, the flight ability is s...Leptinotarsa decemlineata adults exhibit a season-dependent activity. In spring, post-diapause beetles often fly a long distance from overwintering sites to potato fields. In summer and autumn, the flight ability is sharply reduced. Proline is the main energy substrate ofL. decemlineata during flight and proline dehydrogenase （ProDH） catalyzes the first step in proline catabolism. Here we identified a putative LdProDHgene; it had three cDNA isoforms which shared the same 5＇UTR and coding region, but differed in the lengths of 3＇UTRs （515, 1 092 and 1 242 bp for isoforms-1, -2 and -3, respectively）. LdProDH encoded a 616 amino acid protein that showed high sequence similarity to ProDH-like proteins from other insect species. LdProDHwas expressed in the third and fourth instars larvae and adults, but not in pupae. Dietary ingestion of bacterially expressed LdProDH- dsRNA by adults significantly decreased its messenger RNA （mRNA） level, and caused an elevation of free proline content in the hemolymph. Further observation revealed that three canonical polyadenylation signals （AATAAA） were tandemly located in the 3＇UTR of isoform-3. The first, second and third polyadenylation sites gave rise to isoforms-1, -2 and -3, respectively. Analysis of the genomic DNA uncovered that the three isoforms resulted from alternative polyadenylation. The mRNA level of isoform-1, which expressed at low levels in pre-diapause adults, became abundant in post-diapause beetles. It is indicated that the LdProDH expression is fine-tuned through 3＇UTR to control proline catabolism for the season-dependent activity ofL. decemlineata adults.展开更多
Brassinosteroids(BRs)are plant hormones that regulate wood formation in trees.Currently,little is known about the post-transcriptional regulation of BR synthesis.Here,we show that during wood formation,fine-tuning BR ...Brassinosteroids(BRs)are plant hormones that regulate wood formation in trees.Currently,little is known about the post-transcriptional regulation of BR synthesis.Here,we show that during wood formation,fine-tuning BR synthesis requires 3′UTR-dependent decay of Populus CONSTITUTIVE PHOTOMORPHOGENIC DWARF 1(PdCPD1).Overexpression of PdCPD1 or its 3′UTR fragment resulted in a significant increase of BR levels and inhibited secondary growth.In contrast,transgenic poplars repressing PdCPD13′UTR expression displayed moderate levels of BR and promoted wood formation.We show that the Populus GLYCINE-RICH RNA-BINDING PROTEIN1(PdGRP1)directly binds to a GU-rich element in 3′UTR of Pd CPD1,leading to its mRNA decay.We thus provide a post-transcriptional mechanism underlying BRs synthesis during wood formation,which may be useful for genetic manipulation of wood biomass in trees.展开更多
基金supported by the National Basic Research Program of China (973 Program) (No. 2006CB701506 and 2007CB815705)the Chinese Academy of Sciences (No. KSCX1-YW-R-34)+1 种基金the National Natural Science Foundation of China (No. 30525028, 30630013 and 30871343)the Natural Science Foundation of Yunnan Province of China.
文摘MicroRNAs （miRNAs） are endogenous -22 nucleotide noncoding RNAs that regulate the expression of complementary messenger RNAs （mRNAs）. Thousands of miRNA genes have been found in diverse species, and many of them are highly conserved. With the miRNA roles identified in nearly all aspects of biological processes, evidence is mounting that miRNAs could represent a new layer of regulatory network, and their regulatory effect might be much more pervasive than previously suspected. Here we focus on the posttranscriptional level gene regulation of miRNAs in animals and review how the miRNAs act to sustain and shape up the expression profiles of specific cell types; how the miRNAs integrate into the existing gene regulatory networks; and how the miRNAs influence the evolution of 3＇UTR of mammalian mRNAs.
文摘Leptinotarsa decemlineata adults exhibit a season-dependent activity. In spring, post-diapause beetles often fly a long distance from overwintering sites to potato fields. In summer and autumn, the flight ability is sharply reduced. Proline is the main energy substrate ofL. decemlineata during flight and proline dehydrogenase （ProDH） catalyzes the first step in proline catabolism. Here we identified a putative LdProDHgene; it had three cDNA isoforms which shared the same 5＇UTR and coding region, but differed in the lengths of 3＇UTRs （515, 1 092 and 1 242 bp for isoforms-1, -2 and -3, respectively）. LdProDH encoded a 616 amino acid protein that showed high sequence similarity to ProDH-like proteins from other insect species. LdProDHwas expressed in the third and fourth instars larvae and adults, but not in pupae. Dietary ingestion of bacterially expressed LdProDH- dsRNA by adults significantly decreased its messenger RNA （mRNA） level, and caused an elevation of free proline content in the hemolymph. Further observation revealed that three canonical polyadenylation signals （AATAAA） were tandemly located in the 3＇UTR of isoform-3. The first, second and third polyadenylation sites gave rise to isoforms-1, -2 and -3, respectively. Analysis of the genomic DNA uncovered that the three isoforms resulted from alternative polyadenylation. The mRNA level of isoform-1, which expressed at low levels in pre-diapause adults, became abundant in post-diapause beetles. It is indicated that the LdProDH expression is fine-tuned through 3＇UTR to control proline catabolism for the season-dependent activity ofL. decemlineata adults.
基金financially supported by grants from the National Key Scientific Research Project of China(2021YFD2200205)the National Natural Science Foundation of China(31972955,32071725 and 31700526)+2 种基金the Major Science and Technology Innovation Project of Shandong Province(2022LZGC018)Shandong Youth Innovation Team Plan(2022KJ168)the Taishan Scholar Program of Shandong(tsqn202103092)。
文摘Brassinosteroids(BRs)are plant hormones that regulate wood formation in trees.Currently,little is known about the post-transcriptional regulation of BR synthesis.Here,we show that during wood formation,fine-tuning BR synthesis requires 3′UTR-dependent decay of Populus CONSTITUTIVE PHOTOMORPHOGENIC DWARF 1(PdCPD1).Overexpression of PdCPD1 or its 3′UTR fragment resulted in a significant increase of BR levels and inhibited secondary growth.In contrast,transgenic poplars repressing PdCPD13′UTR expression displayed moderate levels of BR and promoted wood formation.We show that the Populus GLYCINE-RICH RNA-BINDING PROTEIN1(PdGRP1)directly binds to a GU-rich element in 3′UTR of Pd CPD1,leading to its mRNA decay.We thus provide a post-transcriptional mechanism underlying BRs synthesis during wood formation,which may be useful for genetic manipulation of wood biomass in trees.
