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Microorganisms are valuable resources for lipid production. What makes one microbe but not the other able to efficiently synthesize and accumulate lipids is poorly understood. In the present study, global gene expression prior to and after the onset of lipogenesis was determined by transcriptomics using the oleaginous fungus Mortierella alpina as a model system. A core of 23 lipogenesis associated genes was identified and their expression patterns shared a high similarity among oleaginous microbes Chlamydomonas reinhardtii, Mucor circinelloides and Rhizopus oryzae but was dissimilar to the non-oleaginous Aspergillus nidulans. Unexpectedly, Glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (PGD) in the pentose phosphate pathway (PPP) were found to be the NADPH producers responding to lipogenesis in the oleaginous microbes. Their role in lipogenesis was confirmed by a knockdown experiment. Our results demonstrate, for the first time, that the PPP plays a significant role during fungal lipogenesis. Up-regulation of NADPH production by the PPP, especially G6PD, may be one of the critical determinants that enables efficiently fatty acid synthesis in oleaginous microbes. [ABSTRACT FROM AUTHOR]

To investigate whether mitochondrial DNA haplogroups M or N are related to occurrence or manifestations of systemic lupus erythematosus (SLE), we collected M/N haplogrouping and clinical characteristics from 868 Han Chinese women with SLE, as well as for 870 age-matched healthy Han Chinese control women. M/N haplogroups were determined in all subjects using allele-specific amplification. The frequency of M haplogroup in all patients was 429 (49.4%) and the frequency of N haplogroup, 439 (50.6%). The corresponding frequencies in controls were 456 (52.4%) and 414 (47.6%) (P = 0.213). Among women older than 50 years at onset age, the N haplogroup was significantly higher in patients than in healthy controls (59.6% vs 41.7%, P = 0.042). The N haplogroup was associated with significantly higher risk for certain SLE characteristics: hematological system damage (OR 2.128, 95%CI 1.610 to 2.813), skin impairment (OR 1.873, 95%CI 1.428 to 2.457), neurological disturbance (OR 3.956, 95%CI 1.874 to 8.352) and alopecia (OR 1.322, 95%CI 1.007 to 1.737 ). Our results suggest that in Han Chinese women, the mtDNA N haplogroup is associated with higher risk of late-onset SLE, skin impairment, neurological disturbance, hematological system damage and alopecia. [ABSTRACT FROM AUTHOR]

Stroke is one of the leading causes of death and long-term disability worldwide. Mitochondrial DNA (mtDNA) is a potential contributor for the sex differences of ischemic stroke heritability. Although mtDNA haplogroups were associated with stroke onset, their impacts on stroke outcomes remain unclear. This study aimed to evaluate the impacts of mtDNA haplogroups on short-term outcomes of neurological functions in patients with ischemic stroke. A total of 303 patients were included, and their clinical data and mtDNA sequences were analyzed. Based on the changes between baseline and 14-day follow-up stroke severity, our results showed that haplogroup N9 was an independent protective factor against neurological worsening in acute ischemic stroke patients. These findings supported that mtDNA variants play a role in post-stroke neurological recovery, thus providing evidences for future pharmacological intervention in mitochondrial function. [ABSTRACT FROM AUTHOR]

Previous stochastic localization-based super-resolution techniques are largely limited by the labeling density and the fidelity to the morphology of specimen. We report on an optical super-resolution imaging scheme implementing joint tagging using multiple fluorescent blinking dyes associated with super-resolution optical fluctuation imaging (JT-SOFI), achieving ultra-high labeling density super-resolution imaging. To demonstrate the feasibility of JT-SOFI, quantum dots with different emission spectra were jointly labeled to the tubulin in COS7 cells, creating ultra-high density labeling. After analyzing and combining the fluorescence intermittency images emanating from spectrally resolved quantum dots, the microtubule networks are capable of being investigated with high fidelity and remarkably enhanced contrast at sub-diffraction resolution. The spectral separation also significantly decreased the frame number required for SOFI, enabling fast super-resolution microscopy through simultaneous data acquisition. As the joint-tagging scheme can decrease the labeling density in each spectral channel, thereby bring it closer to single-molecule state, we can faithfully reconstruct the continuous microtubule structure with high resolution through collection of only 100 frames per channel. The improved continuity of the microtubule structure is quantitatively validated with image skeletonization, thus demonstrating the advantage of JT-SOFI over other localization-based super-resolution methods. [ABSTRACT FROM AUTHOR]