The Experts below are selected from a list of 99 Experts worldwide ranked by ideXlab platform
Caterina Mencarelli - One of the best experts on this subject based on the ideXlab platform.
-
Autosomal control of the Y-chromosome kl-3 loop of Drosophila melanogaster
Chromosoma, 2004Co-Authors: Roberto Piergentili, Silvia Bonaccorsi, Grazia Daniela Raffa, Claudio Pisano, Johannes H. P. Hackstein, Caterina MencarelliAbstract:The Y chromosome of Drosophila melanogaster carries a limited number of loci necessary for male Fertility that possess a series of unconventional features that still hinder a definition of their biological role: they have extremely large sizes; accommodate huge amounts of repetitive DNA; and develop prominent, lampbrush-like loops that bind a number of non-Y-encoded proteins. To obtain insight into the functional role of the loop-forming Fertility Factors, we characterized four autosomal male-sterile mutations that identify two loci we named loop unfolding protein-1 (lup-1) and loop unfolding protein-2 (lup-2) . Biochemical and ultrastructural analysis revealed that neither of them impairs the synthesis of the putative dynein subunit encoded by the ORF localized within the kl-3 Fertility Factor. However, the stability of four dynein heavy chains is simultaneously affected in each mutant, together with the regular assembly of the axonemal dynein arms that are either absent or strongly reduced. These results indicate that the synthesis of the kl-3 -encoded dynein can be uncoupled from the formation of the corresponding loop and suggest that this structure does not simply represent the cytological counterpart of a huge transcription unit, but must be regarded as a complex organelle serving some additional function necessary for male Fertility.
Craig Montell - One of the best experts on this subject based on the ideXlab platform.
-
The Role of Y Chromosome Genes in Male Fertility in Drosophila melanogaster.
Genetics, 2020Co-Authors: Jiaying Zhang, Junjie Luo, Jieyan Chen, Junbiao Dai, Craig MontellAbstract:The Y chromosome of Drosophila melanogaster is pivotal for male Fertility. Yet, only 16 protein-coding genes reside on this chromosome. The Y chromosome is comprised primarily of heterochromatic sequences, including DNA repeats and satellite DNA, and most of the Y chromosome is still missing from the genome sequence. Furthermore, the functions of the majority of genes on the Y chromosome remain elusive. Through multiple genetic strategies, six distinct segments on the Y chromosome have been identified as "male Fertility Factors," and candidate gene sequences corresponding to each of these loci have been ascribed. In one case, kl-3, a specific protein coding sequence for a Fertility Factor has been confirmed molecularly. Here, we employed CRISPR/Cas9 to generate mutations, and RNAi, to interrogate the requirements of protein coding sequences on the Y chromosome for male Fertility. We show that CRISPR/Cas9-mediated editing of kl-2 and kl-5 causes male sterility, supporting the model that these gene sequences correspond to the cognate Fertility Factors. We show that another gene, CCY, also functions in male Fertility and may be the ks-2 Fertility Factor. We demonstrate that editing of kl-2, kl-3, and kl-5, and RNAi knockdown of CCY, disrupts nuclear elongation, and leads to defects in sperm individualization, including impairments in the individualization complex (IC) and synchronization. However, CRISPR/Cas9 mediated knockout of some genes on the Y chromosome, such as FDY, Ppr-Y, and Pp1-Y2 do not cause sterility, indicating that not all Y chromosome genes are essential for male Fertility.
Ruirui Peng - One of the best experts on this subject based on the ideXlab platform.
-
the 5 8s pre rrna maturation Factor m phase phosphoprotein 6 is a female Fertility Factor required for oocyte quality and meiosis
Cell Proliferation, 2020Co-Authors: Ruirui Peng, Lili Wang, Wenyi Gao, Fengyu Zhu, Wentao Zeng, Liya Shi, Xichen Chen, Jingyang Cai, Dong ZhangAbstract:Objectives M-phase phosphoprotein 6 (MPP6) is important for 5.8S pre-rRNA maturation in somatic cells and was screened as a female Fertility Factor. However, whether MPP6 functions in oocyte meiosis and Fertility is not yet known. We aimed to address this. Materials and methods Mouse oocytes with surrounded nucleus (SN) or non-surrounded nucleus (NSN) were used for all experiments. Peptide nanoparticle-mediated antibody transfection was used to deplete MPP6. Immunofluorescence staining, immunohistochemistry and live tracker staining were used to examine MPP6 localization and characterize phenotypes after control or MPP6 depletion. High-fidelity PCR and fluorescence in situ hybridization (FISH) were used to examine the localization and level of 5.8S rRNAs. Western blot was used to examine the protein level. MPP6-EGFP mRNA microinjection was used to do the rescue. Results MPP6 was enriched within ovaries and oocytes. MPP6 depletion significantly impeded oocyte meiosis. MPP6 depletion increased 5.8S pre-rRNA. The mRNA levels of MPP6 and 5.8S rRNA decreased within ageing oocytes, and MPP6 mRNA injection partially increased 5.8S rRNA maturation and improved oocyte quality. Conclusions MPP6 is required for 5.8S rRNA maturation, meiosis and quality control in mouse oocytes, and MPP6 level might be a marker for oocyte quality.
Roberto Piergentili - One of the best experts on this subject based on the ideXlab platform.
-
Autosomal control of the Y-chromosome kl-3 loop of Drosophila melanogaster
Chromosoma, 2004Co-Authors: Roberto Piergentili, Silvia Bonaccorsi, Grazia Daniela Raffa, Claudio Pisano, Johannes H. P. Hackstein, Caterina MencarelliAbstract:The Y chromosome of Drosophila melanogaster carries a limited number of loci necessary for male Fertility that possess a series of unconventional features that still hinder a definition of their biological role: they have extremely large sizes; accommodate huge amounts of repetitive DNA; and develop prominent, lampbrush-like loops that bind a number of non-Y-encoded proteins. To obtain insight into the functional role of the loop-forming Fertility Factors, we characterized four autosomal male-sterile mutations that identify two loci we named loop unfolding protein-1 (lup-1) and loop unfolding protein-2 (lup-2) . Biochemical and ultrastructural analysis revealed that neither of them impairs the synthesis of the putative dynein subunit encoded by the ORF localized within the kl-3 Fertility Factor. However, the stability of four dynein heavy chains is simultaneously affected in each mutant, together with the regular assembly of the axonemal dynein arms that are either absent or strongly reduced. These results indicate that the synthesis of the kl-3 -encoded dynein can be uncoupled from the formation of the corresponding loop and suggest that this structure does not simply represent the cytological counterpart of a huge transcription unit, but must be regarded as a complex organelle serving some additional function necessary for male Fertility.
Josef Altenbuchner - One of the best experts on this subject based on the ideXlab platform.
-
Streptomyces coelicolor A3(2) plasmid SCP2*: deductions from the complete sequence.
Microbiology, 2003Co-Authors: Iris Haug, Tobias Kieser, Anke Weissenborn, Dirk Brolle, Stephen D. Bentley, Josef AltenbuchnerAbstract:Plasmid SCP2* is a 31 kb, circular, low-copy-number plasmid originally identified in Streptomyces coelicolor A3(2) as a Fertility Factor. The plasmid was completely sequenced. The analysis of the 31 317 bp sequence revealed 34 ORFs encoding putative proteins from 31 to 710 aa long, most of them lacking similarity to known proteins. Three functional regions had been identified previously: the replication region, the transfer and spreading region, and the stability region. Three genes were identified in the stability region which contribute to the stability of SCP2 as shown by plasmid stability testing. The first gene, mrpA, encodes a new member of the λ integrase family of site-specific recombinases. The two genes downstream of mrpA were called parA and parB. The gene product, ParA, shows similarity to a family of ATPases involved in plasmid partition. An increase of plasmid stability could be seen only when both genes were present. By deletion analysis, the replication region could be narrowed down to a 1·6 kb region, consisting of a 650 bp non-coding region and two genes, repI and repII, encoding proteins of 161 and 131 aa. Only RepI exhibits similarities to DNA binding elements and contains a putative helix–turn–helix motif. The traA gene that is essential for DNA transfer and pock formation was identified previously. Upstream of traA, 10 ORFs were found in the same orientation as traA which might be involved in conjugation and DNA spreading, together with one gene in the opposite orientation with similarities to transcriptional regulators of DNA transfer. Two transposable elements were found on SCP2*. IS1648 belongs to the IS3 family of insertion sequences. The second element, Tn5417, shows the highest similarity to the Tn4811 element located in the terminal inverted repeats of the Streptomyces lividans chromosome.