Sound waves are converted into electric signals by hair bundles(also known as stereocilia)in the cochlear hair cells.Stereocilia,a cluster of actin protrusions at the apical surface of hair cells,are organized into ro...Sound waves are converted into electric signals by hair bundles(also known as stereocilia)in the cochlear hair cells.Stereocilia,a cluster of actin protrusions at the apical surface of hair cells,are organized into rows of graded height(Figure 1).Mechanical force induced by sound waves leads to stereocilia deflection towards the tallest row and subsequent activation of mechanoelectrical transducer channels at the tips of the shorter rows,thus achieving mechanoelectrical transduction(Gillespie and Muller,2009).Such a staircase-like architecture is essential for auditory perception as manifested by severe deafness caused by genetic mutations that disrupt stereocilia morphology(Barr-Gillespie,2015).However,little is known about how this planar asymmetry of stereocilia is achieved.展开更多
Mitochondria in many fungi are inherited uniparentally during meiosis. It has remained unclear whether parental mitochondria in the fission yeast Schizosaccharomyces pombe are inherited uniparentally or biparentally. ...Mitochondria in many fungi are inherited uniparentally during meiosis. It has remained unclear whether parental mitochondria in the fission yeast Schizosaccharomyces pombe are inherited uniparentally or biparentally. Here, we assessed the mixing of parental mitochondria carefully by live-cell microscopy and developed an algorithm to determine the degree of mitochondrial mixing in a quantitative manner. We found that parental mitochondria in fission yeast cells were mixed progressively as meiosis progressed. Moreover, we established that mitochondrial fission and the size of the conjugation neck are the limiting factors in restricting the mixing of parental mitochondria. We further employed a combination of quantitative polymerase chain reaction, fluorescent live-cell microscopy, and transmission electron microscopy approaches to examine the mitochondrial inheritance of progeny cells derived from a cross between wild-type and Rho0 (mitochondrial DNA absent) cells. The results show that all progeny cells of the cross carry mitochondrial DNA. Hence, our data support the model in which parental mitochondria in the fission yeast S. pombe are inherited biparentally during meiosis.展开更多
基金This work was supported by grants from the National Key R&D Program of China(2018YFA0507900 to 1.Z,2019YFA0508402 to C.W.)the National Natural Science Foundation of China(32122036,U2032122,and 31770779 to 1.Z+3 种基金22122703,91953110,and 32170767 to C.W.)the Science and Technology Commission of Shanghai Municipality(20S 11900200)the Interdisciplinary Innovative Talent Training Program of Shanghai Jiao Tong University(to 1.Z.)the Scientific Research Foundation for Youth Scholars of Shanghailiao Tong University(AF0890029 to L.L.)。
文摘Sound waves are converted into electric signals by hair bundles(also known as stereocilia)in the cochlear hair cells.Stereocilia,a cluster of actin protrusions at the apical surface of hair cells,are organized into rows of graded height(Figure 1).Mechanical force induced by sound waves leads to stereocilia deflection towards the tallest row and subsequent activation of mechanoelectrical transducer channels at the tips of the shorter rows,thus achieving mechanoelectrical transduction(Gillespie and Muller,2009).Such a staircase-like architecture is essential for auditory perception as manifested by severe deafness caused by genetic mutations that disrupt stereocilia morphology(Barr-Gillespie,2015).However,little is known about how this planar asymmetry of stereocilia is achieved.
基金supported by grants from the National Natural Science Foundation of China(91754106,31621002,31871350,and 32070707)the Natural Science Key Project of Anhui Institution of Higher Education(KJ2020A0441).
文摘Mitochondria in many fungi are inherited uniparentally during meiosis. It has remained unclear whether parental mitochondria in the fission yeast Schizosaccharomyces pombe are inherited uniparentally or biparentally. Here, we assessed the mixing of parental mitochondria carefully by live-cell microscopy and developed an algorithm to determine the degree of mitochondrial mixing in a quantitative manner. We found that parental mitochondria in fission yeast cells were mixed progressively as meiosis progressed. Moreover, we established that mitochondrial fission and the size of the conjugation neck are the limiting factors in restricting the mixing of parental mitochondria. We further employed a combination of quantitative polymerase chain reaction, fluorescent live-cell microscopy, and transmission electron microscopy approaches to examine the mitochondrial inheritance of progeny cells derived from a cross between wild-type and Rho0 (mitochondrial DNA absent) cells. The results show that all progeny cells of the cross carry mitochondrial DNA. Hence, our data support the model in which parental mitochondria in the fission yeast S. pombe are inherited biparentally during meiosis.
