Li, Ruixi* Dotaz Zobrazit nápovědu
Plant architecture is one of the key factors that affect plant survival and productivity. Plant body structure is established through the iterative initiation and outgrowth of lateral organs, which are derived from the shoot apical meristem and root apical meristem, after embryogenesis. Here we report that ADP1, a putative MATE (multidrug and toxic compound extrusion) transporter, plays an essential role in regulating lateral organ outgrowth, and thus in maintaining normal architecture of Arabidopsis. Elevated expression levels of ADP1 resulted in accelerated plant growth rate, and increased the numbers of axillary branches and flowers. Our molecular and genetic evidence demonstrated that the phenotypes of plants over-expressing ADP1 were caused by reduction of local auxin levels in the meristematic regions. We further discovered that this reduction was probably due to decreased levels of auxin biosynthesis in the local meristematic regions based on the measured reduction in IAA levels and the gene expression data. Simultaneous inactivation of ADP1 and its three closest homologs led to growth retardation, relative reduction of lateral organ number and slightly elevated auxin level. Our results indicated that ADP1-mediated regulation of the local auxin level in meristematic regions is an essential determinant for plant architecture maintenance by restraining the outgrowth of lateral organs.
- MeSH
- Arabidopsis genetika růst a vývoj MeSH
- kořeny rostlin genetika růst a vývoj metabolismus MeSH
- květy genetika růst a vývoj MeSH
- kyseliny indoloctové metabolismus MeSH
- meristém růst a vývoj metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- proteiny přenášející organické kationty genetika MeSH
- regulace genové exprese u rostlin MeSH
- výhonky rostlin genetika růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Prenatal exposure to caffeine can cause developmental problems. This study determined chronic influence of prenatal caffeine at relatively higher doses on cognitive functions in the rat offspring. Pregnant Sprague-Dawley rats (4-month-old) were exposed to caffeine (20 mg/kg, twice a day) for whole pregnancy from gestational day 4. Fetal and offspring body and brain weight was measured. Learning and memory were tested in adult offspring with Morris water maze. Learning and memory-related receptors were measured. The exposure to prenatal caffeine not only caused fetal growth restriction, but also showed long-term effects on learning and memory in the offspring. The caffeine offspring exhibited longer escape latency and path length in navigation testing. The number of passing the target was significantly reduced in those offspring. The expression of adenosine A(1) and A(2A) receptors, nuclear PKA C(alpha), C(beta) subunits, and pCREB were significantly increased in the fetal and neonatal brain, and suppressed in the hippocampus of the adult offspring. The expression of BDNF and TrkB were reduced regardless of various ages. The results suggest that intrauterine programming dysfunction of adenosine receptors and the down-stream of cAMP/PKA/pCREB system may play an important role in prenatal caffeine induced cognition disorders in the adult offspring.
- MeSH
- bludiště - učení účinky léků fyziologie MeSH
- kofein toxicita MeSH
- krysa rodu rattus MeSH
- mozkový neurotrofický faktor metabolismus MeSH
- paměť účinky léků fyziologie MeSH
- poruchy paměti chemicky indukované diagnóza metabolismus MeSH
- potkani Sprague-Dawley MeSH
- protein vázající cAMP responzivní element metabolismus MeSH
- proteinkinasy závislé na cyklickém AMP metabolismus MeSH
- purinergní receptory P1 metabolismus MeSH
- signální transdukce účinky léků fyziologie MeSH
- těhotenství MeSH
- zpožděný efekt prenatální expozice chemicky indukované diagnóza metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The incidence of cerebrovascular diseases increases significantly with aging. This study aimed to test the hypothesis that aging may influence the protein kinase A (PKA)-dependent vasodilation via RyR/BKCa pathway in the middle cerebral arteries (MCA). Male Sprague-Dawley rats were randomly divided into control (4-6 month-old) and aged (24-month-old) groups. The functions of MCA and ion channel activities in smooth muscle cells were examined using myograph system and patch-clamp. Aging decreased the isoproterenol/forskolin-induced relaxation in the MCA. Large-conductance Ca(2+)-activated-K(+) (BKCa) channel inhibitor, iberiotoxin, significantly attenuated the forskolin-induced vasodilatation and hyperpolarization in the young group, but not in the aged group. The amplitude and frequency of spontaneous transient outward currents (STOCs) were significantly decreased in the aged group. Single channel recording revealed that the mean open time of BKCa channels were decreased, while an increased mean closed time of BKCa channels were found in the aged group. The Ca(2+)/voltage sensitivity of the channels was decreased accompanied by reduced BKCa alpha and beta1-subunit, the expression of RyR2, PKA-Calpha and PKA-Cbeta subunits were also declined in the aged group. Aging induced down-regulation of PKA/BKCa pathway in cerebral artery in rats. The results provides new information on further understanding in cerebrovascular diseases resulted from age-related cerebral vascular dysfunction.
- MeSH
- arteriae cerebrales * fyziologie MeSH
- down regulace MeSH
- kolforsin MeSH
- krysa rodu rattus MeSH
- potkani Sprague-Dawley MeSH
- proteinkinasy závislé na cyklickém AMP * MeSH
- stárnutí MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The exocyst complex regulates the last steps of exocytosis, which is essential to organisms across kingdoms. In humans, its dysfunction is correlated with several significant diseases, such as diabetes and cancer progression. Investigation of the dynamic regulation of the evolutionarily conserved exocyst-related processes using mutants in genetically tractable organisms such as Arabidopsis thaliana is limited by the lethality or the severity of phenotypes. We discovered that the small molecule Endosidin2 (ES2) binds to the EXO70 (exocyst component of 70 kDa) subunit of the exocyst complex, resulting in inhibition of exocytosis and endosomal recycling in both plant and human cells and enhancement of plant vacuolar trafficking. An EXO70 protein with a C-terminal truncation results in dominant ES2 resistance, uncovering possible distinct regulatory roles for the N terminus of the protein. This study not only provides a valuable tool in studying exocytosis regulation but also offers a potentially new target for drugs aimed at addressing human disease.
- MeSH
- Arabidopsis metabolismus MeSH
- buněčná membrána metabolismus MeSH
- endozomy metabolismus MeSH
- exocytóza * MeSH
- konzervovaná sekvence MeSH
- lidé MeSH
- limoniny metabolismus MeSH
- molekulární evoluce MeSH
- proteiny huseníčku chemie genetika metabolismus MeSH
- sekundární struktura proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
OBJECTIVE: To investigate the function of a novel primate-specific long non-coding RNA (lncRNA), named FLANC, based on its genomic location (co-localised with a pyknon motif), and to characterise its potential as a biomarker and therapeutic target. DESIGN: FLANC expression was analysed in 349 tumours from four cohorts and correlated to clinical data. In a series of multiple in vitro and in vivo models and molecular analyses, we characterised the fundamental biological roles of this lncRNA. We further explored the therapeutic potential of targeting FLANC in a mouse model of colorectal cancer (CRC) metastases. RESULTS: FLANC, a primate-specific lncRNA feebly expressed in normal colon cells, was significantly upregulated in cancer cells compared with normal colon samples in two independent cohorts. High levels of FLANC were associated with poor survival in two additional independent CRC patient cohorts. Both in vitro and in vivo experiments demonstrated that the modulation of FLANC expression influenced cellular growth, apoptosis, migration, angiogenesis and metastases formation ability of CRC cells. In vivo pharmacological targeting of FLANC by administration of 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine nanoparticles loaded with a specific small interfering RNA, induced significant decrease in metastases, without evident tissue toxicity or pro-inflammatory effects. Mechanistically, FLANC upregulated and prolonged the half-life of phosphorylated STAT3, inducing the overexpression of VEGFA, a key regulator of angiogenesis. CONCLUSIONS: Based on our findings, we discovered, FLANC as a novel primate-specific lncRNA that is highly upregulated in CRC cells and regulates metastases formation. Targeting primate-specific transcripts such as FLANC may represent a novel and low toxic therapeutic strategy for the treatment of patients.
- MeSH
- farmakogenomické testování MeSH
- genetická terapie MeSH
- genetické markery MeSH
- karcinogeneze * účinky léků genetika MeSH
- kolorektální nádory * genetika terapie MeSH
- lidé MeSH
- myši MeSH
- nádorové biomarkery genetika metabolismus MeSH
- objevování léků MeSH
- patologická angiogeneze * genetika metabolismus MeSH
- proliferace buněk * účinky léků genetika MeSH
- regulace genové exprese u nádorů MeSH
- RNA dlouhá nekódující * genetika metabolismus MeSH
- transkripční faktor STAT3 metabolismus MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH