Biology subjects

Ma, J.-Y.

Publications and source records attributed to Ma, J.-Y..

3 recordsLinked to original sources

bioRxiv2020

Cholecystokinin-like Peptide Mediates Satiety by Inhibiting Sugar Attraction

Feeding is essential for animal survival and reproduction and is regulated by both internal states and external stimuli. However, little is known about how internal states influence the perception of external sensory cues that regulate feeding behavior. Here, we investigated the neuronal and molecular mechanisms behind nutritional state-mediated regulation of gustatory perception in control of feeding behavior in the brown planthopper and Drosophila. We found that feeding increases the expression of the cholecystokinin-like peptide, sulfakinin (SK), and the activity of a set of SK-expressing neurons. Starvation elevates the transcription of the sugar receptor Gr64f and SK negatively regulates the expression of Gr64f in both insects. This Gr64f regulation is by direct action of SK neurons on Gr64f-expressing neurons of the proboscis and proleg tarsi that co-express the SK receptor CCKLR-17D3. Our findings thus demonstrate how nutritional state induces peptide signaling to modulate sweet perception and thereby feeding behavior.

neuroscience↗

bioRxiv2020

Double-strand breaks can induce DNA replication and damage amplification in G2 phase-like oocytes of mice

Break-induced DNA replication (BIR) have been detected not only in the genome of rare disease patients but also in cancer cells, however, the mechanisms of BIR formation havent been explained in details. In the late G2 phase-like mouse oocytes, we found DNA double-strand breaks (DSBs) could induce Rad51 dependent small-scale DNA replication. In addition, we also found the DSBs could be amplified in mouse oocytes, and the amplification could be inhibited by Rad51 inhibitor IBR2 and DNA replication inhibitor ddATP. Lastly, we found the DSB repair was relatively inefficiency in hybrid mouse oocytes compared with that of the purebred mouse oocytes. We found DSBs could induce BIR more easier in hybrid mouse oocytes, indicating the DNA repair in oocytes could be affected by the sequence differences between homologous chromatids. In summary, our results indicated that the condensed chromatin configuration in late G2 phase and the sequence similarity between broken DNA and template DNA are causing factors of BIR in mammalian genome, and the DNA damage could be amplified in late G2 phase cells.

genetics↗

bioRxiv2020

Single cell RNA sequencing reveals the landscape of early female germ cell development

Female germ cell development consists of complex events including sex determination, meiosis initiation, retardation and resumption. During early oogenesis, the asynchrony of the transition from mitosis to meiosis results in heterogeneity in the female germ cell populations at a certain embryonic stage, which limits the studies of meiosis initiation and progression at a higher resolution level. Here, we investigated the transcriptional profiles of 19363 single germ cells collected from E12.5, E14.5 and E16.5 mouse fetal ovaries. Clustering analysis identified seven groups and defined dozens of corresponding transcription factors, providing a global view of cellular differentiation from primordial germ cells towards meiocytes. Further, we explored the dynamics of gene expression within the developmental trajectory with special focus on the mechanisms underlying meiotic initiation. We found that Dpy30 may be involved in the regulation of meiosis initiation at the epigenetic level. Our data provide key insights into the transcriptome features of peri-meiotic female germ cells, which offers new information not only on meiosis initiation and progression but also on screening pathogenic mutations in meiosis-associated diseases.

developmental biology↗