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Glioma is a malignant tumor that affects all kinds of people all over the world. It demonstrates remarkable infiltrative and invasive features. The high expression of interleukin-13 receptor subunit alpha-2 (IL-13Rα2) reportedly plays a pivotal role in some cancers. However, whether IL-13Rα2 contributes to glioma remains unknown. This study demonstrates that IL-13Rα2 is significantly up-regulated in human glioma tissue samples. It is also associated with late stages of disease progression and diminished survival in glioma patients. Gain- and loss-of-function studies demonstrate that IL-13Rα2 promotes the growth, migration, and invasion of glioma cells. In addition, mechanistic investigations show that IL-13Rα2 activates Scr, phosphatidylinositol 3 kinase (PI3K), Akt, and mTOR. Also, restraining Scr in glioma cells attenuates the activation of Scr/PI3K/Akt/mTOR pathway by IL-13Rα2, whereas the silencing of Scr markedly rescues the pro-invasive effect of IL-13Rα2. In conclusion, our results suggest that the high expression of IL-13Rα2 is significantly associated with the growth and metastasis of human glioma cells via the Scr/PI3K/Akt/mTOR pathway, while IL-13Rα2 may be a potential therapeutic target for glioma treatment.

Photoperiod and temperature are two pivotal regulatory factors of plant flowering. The floral transition of plants depends on accurate measurement of changes in photoperiod and temperature. The flowering time of rice (Oryza sativa) as a facultative short-day (SD) plant is delayed under long-day (LD) and/or low temperature conditions. To elucidate the regulatory functions of photoperiod and temperature on flowering time in rice, we systematically analyzed the expression and regulation of several key genes (Hd3a, RFT1, Ehd1, Ghd7, RID1/Ehd2/OsId1, Se5) involved in the photoperiodic flowering regulatory pathway under different temperature and photoperiod treatments using a photoperiod-insensitive mutant and wild type plants. Our results indicate that the Ehd1-Hd3a/RFT1 pathway is common to and conserved in both the photoperiodic and temperature flowering regulatory pathways. Expression of Ehd1, Hd3a and RFT1 is dramatically reduced at low temperature (23°C), suggesting that suppression of Ehd1, Hd3a and RFT1 transcription is an essential cause of delayed flowering under low temperature condition. Under LD condition, Ghd7 mRNA levels are promoted at low temperature (23°C) compared with normal temperature condition (28°C), suggesting low temperature and LD treatment have a synergistic role in the expression of Ghd7. Therefore, upregulation of Ghd7 might be a crucial cause of delayed flowering under low temperature condition. We also analyzed Hd1 regulatory relationships in the photoperiodic flowering pathway, and found that Hd1 can negatively regulate Ehd1 transcription under LD condition. In addition, Hd1 can also positively regulate Ghd7 transcription under LD condition, suggesting that the heading-date of rice under LD condition is also regulated by the Hd1-Ghd7-Ehd1-RFT1 pathway. rice, photoperiod, temperature, flowering regulation, interaction Citation:Song Y L, Gao Z C, Luan W J. Interaction between temperature and photoperiod in regulation of flowering time in rice. Sci China Life Sci, 2012Sci, , 55: 241 -249, doi: 10.1007 Crop yields are strongly associated with flowering time. The floral transition of crops depends mainly on the accurate measurement of changes in day length (photoperiod) and temperature, which is regulated by both endogenous genes and environmental factors. Plants can perceive and respond to changes in photoperiod [1,2]. Recent molecular biological work reveals that the rice (Oryza sativa) genes Heading date 3a (Hd3a) and Rice FT-like 1 (RFT1), orthologs of Arabidopsis FLOWERING LOCUS T (FT), encode florigens that can move from the leaf to the shoot apical meristem (SAM) and induce flowering in plants [3][4][5]. Under short-day (SD) conditions, expression of Hd3a promotes rice flowering by the OsGI-Heading date 1(Hd1)-Hd3a pathway which is conserved with the GIGANTEA (GI)-CONSTANS (CO)-FT pathway in Arabidopsis [3,6,7]. In this pathway, Hd1 is an ortholog of CO in Arabidopsis, and encodes a transcription factor with a zinc finger domain, serving as a promoter of rice flowering under SD con...

So far, it has been still unknown how liamocins are biosynthesized, regulated, transported and secreted. In this study, a highly reducing polyketide synthase (HR-PKS), a mannitol- 1-phosphate dehydrogenase (MPDH), a mannitol dehydrogenase (MtDH), an arabitol dehydrogenase (ArDH) and an esterase (Est1) were found to be closely related to core biosynthesis of extracellular liamocins in Aureobasidium melanogenum 6-1-2. The HR-PKS was responsible for biosynthesis of 3,5-dihydroxydecanoic acid. The MPDH and MtDH were implicated in mannitol biosynthesis and the ArDH was involved in arabitol biosynthesis. The Est1 catalyzed ester bond formation of them. A phosphopantetheine transferase (PPTase) activated the HR-PKS and a transcriptional activator Ga11 activated expression of the PKS1 gene. Therefore, deletion of the PKS1 gene, all the three genes encoding MPDH, MtDH and ArDH, the EST1, the gene responsible for PPTase and the gene for Ga11 made all the disruptants (Dpks13, Dpta13, Dest1, Dp12 and Dg11) totally lose the ability to produce any liamocins. A GLTP gene encoding a glycolipid transporter and a MDR1 gene encoding an ABC transporter took part in transport and secretion of the produced liamocins into medium. Removal of the GLTP gene and the MDR1 gene resulted in a Dgltp1 mutant and a Dmdr16 mutant, respectively, that lost the partial ability to secrete liamocins, but which cells were swollen and intracellular lipid accumulation was greatly enhanced. Hydrolysis of liamocins released 3,5-dihydroxydecanoic acid, mannitol, arabitol and acetic acid. We proposed a core biosynthesis pathway, regulation, transport and secretion of liamocins in A. melanogenum.