Biology subjects

Diao, F.

Publications and source records attributed to Diao, F..

4 recordsLinked to original sources

bioRxiv2021

piRNA pathway is essential for generating functional oocytes in golden hamster

Piwi-interacting RNAs (piRNAs) are small RNAs predominantly expressed in germ cells that are critical for gametogenesis in various species. However, PIWI-deficient female mice are fertile and mouse oocytes express a panel of small RNAs that do not appear widely representative of mammals, and piRNA function in the oogenesis of other mammals has therefore remained elusive. Recent studies revealed the small RNA and PIWI transcriptional profiles in golden hamster oocytes more closely resemble that of humans than mice. Herein, we generated PIWIL1-, PLD6- and MOV10L1-deficient golden hamsters and found that all female mutants were sterile, with embryos arrested at the two-cell stage. In PIWIL1 mutant oocytes, we observed transposon accumulation and broad transcriptomic dysregulation, while zygotic gene activation was impaired in early embryos. Intriguingly, PIWIL1-piRNAs exhibited a unique, preferential silencing of endogenous retroviruses (ERVs), whereas silencing LINE1s depended on both PIWIL1- and PIWIL3-piRNAs. Moreover, we showed that piRNAs participate in the degradation of maternal mRNAs in MII oocytes and embryos via partially complementary targets. Together, our findings demonstrate that piRNAs are indispensable for generating functional oocytes in golden hamster, and show the informative value of this model for functional and mechanistic investigations of piRNAs, especially those related to female infertility.

developmental biology↗

bioRxiv2020

Neuromodulation Exerts Feedback and Feedforward Control of Action Selection

To be effective, behavioral choices must result in actions that are appropriate to an animals needs and environmental circumstances. In addition, the actions must be ones the animal can sustain until its needs are met. This aligning of goals, action, and motivation requires the coordinated activity of multiple brain circuits, but how such coordination is achieved is poorly understood. Here, we show how the insect hormone Bursicon coordinates the selection and sustains execution of a behavior in newly emerged adult Drosophila. Such flies must expand and harden their wings after metamorphosis, but they choose to delay expansion in confined conditions. We show that the decision to expand is mediated by an environmentally-sensitive, positive feedback loop in which Bursicon promotes its own sustained release. Released Bursicon then modulates motor neurons to promote wing expansion behavior. Bursicon thus exerts feedforward and feedback control to coordinately select and motivate a goal-directed action.

neuroscience↗

bioRxiv2020

Microbubble-Mediated Cavitation Promotes Apoptosis and Suppresses Invasion in AsPC-1 Cells

This study aimed to identify the potential and mechanisms of microbubble-mediated cavitation in promoting apoptosis and suppressing invasion in cancer cells. AsPC-1 cells were used and divided into four groups: control group, microbubble-only (MB) group, ultrasound-only (US) group, and ultrasound combined with microbubbles (US+MB) group. Pulse ultrasound was used with a frequency of 360 kHz and an intensity of 0.7 W/cm2 for 1 min (duty rate=50%). Then cells in four groups were cultured for 24 h. Cell counting kit-8 illustrated that US+MB could decrease cell viability. Western blot confirmed that US+MB increased cleaved Caspase-3, Bcl-2-associated X protein (BAX), and decreased the B-cell lymphoma-2 (Bcl-2) levels. Besides, US+MB increased intracellular calcium ions and down-regulated cleaved Caspase-8. For proliferation ability, cells in US+MB group had a lower expression of Ki67 and the weakened colony formation ability. The transwell invasion assay showed that US+MB could decrease invasion ability in AsPC-1 cells. Further evidence showed that cells conducted with US+MB had the lower level of hypoxia-inducible factor-1 (HIF-1) and Vimentin and the higher expression of E-cadherin than the other three groups. Finally, cells conducted with US+MB had less invadopodia formation. In conclusion, these results suggested that microbubble-mediated cavitation promoted apoptosis and suppressed invasion in AsPC-1 cells. SignificanceCancer cells have a high rate of cell division and a high rate of cell division can speed up the development of hypoxia which lead to promote cancer invasion and metastasis. Here we used microbubble-mediated cavitation to generate a mechanical shock wave which could effectively kill cancer cells through physical damage and intrinsic signaling pathway. Furthermore, effective killing of cancer cells could restrain the development of hypoxia and prevent invasion ability of cancer cells.

bioengineering↗

bioRxiv2019

Temporal control of inhibition via muscarinic acetylcholine receptor signaling generates ON and OFF selectivity in a simple visual circuit

ON and OFF selectivity in visual processing is encoded by parallel pathways that respond to either increments or decrements of light. Despite lacking anatomical features to support split channels, Drosophila larvae effectively perform visually-guided behaviors. To understand principles guiding visual computation in this simple circuit, we focus on the physiological properties and behavioral relevance of larval visual interneurons and elucidate their functions in visual processing. We find that the ON vs. OFF discrimination in the larval visual circuit emerges through light-elicited cholinergic signaling that depolarizes the cholinergic interneuron (cha-lOLP) and hyperpolarizes the glutamatergic interneuron (glu-lOLP). Genetic studies further indicate that muscarinic acetylcholine receptor (mAchR)/Go signaling in glu-lOLP separates the ON and OFF signals through temporal delays, the disruption of which strongly impacts both physiological responses of downstream projection neurons and dark-induced pausing behavior. Together, our studies identify cellular and molecular substrates for OFF detection in the larval visual circuit and suggests temporal control of inhibition functions as an effective strategy in generating ON and OFF selectivity without anatomical segregation.

neuroscience↗