Selection for ovulation rate in rabbits: Direct and correlated responses estimated with a cryopreserved control population1

The aim of this work was to evaluate the response in 10 generations of selection for ovulation rate in rabbits using a cryopreserved control population. Selection was based on the phenotypic value of ovulation rate estimated at d 12 of second gestation by laparoscopy. To produce the control population, embryos from 50 donor females and 18 males, belonging to the base generation of the line selected for ovulation rate, were recovered. A total of 467 embryos (72-h embryos) were vitrifi ed and stored in liquid N2 for 10 generations. The size of both populations was approximately 10 males and 50 females. The number of records used to analyze the different traits ranged from 99 to 340. Data were analyzed using Bayesian methodology. A difference between the selected and the control populations of 2.1 ova (highest posterior density interval (HPD95%) [1.3, 2.9]) was observed in ovulation rate (OR), but it was not accompanied by a correlated response in litter size (LS; −0.3; HPD95% [−1.1, 0.5]). The number of implanted embryos (IE) increased with selection in 1.0 embryo (HPD95% [−0.6, 2.0]), but this increase was not relevant. Prenatal survival, embryonic survival, and fetal survival (FS) were calculated as LS/OR, IE/OR, and LS/IE, respectively. Prenatal survival was reduced with selection (−0.12; HPD95% [−0.20, −0.04]), basically because of a decrease in FS (−0.12; HPD95% [−0.19, −0.06]). Embryonic survival could have slightly decreased (−0.05; HPD95% [−0.12, 0.02]). In summary, comparison with a control population showed that ovulation rate in rabbits increased with selection without any correlated response in litter size, basically because of a decrease in fetal survival.This study was supported by the Comision Interministerial de Ciencia y Tecnologia CICYT-AGL2005-07624-C03-01 and by funds from the Generalitat Valenciana research program (Prometeo 2009/125). The authors are grateful to Wagdy Mekkawy for letting us use his programs.Laborda Vidal, P.; Santacreu Jerez, MA.; Blasco Mateu, A.; Mocé Cervera, ML. (2015). Selection for ovulation rate in rabbits: Direct and correlated responses estimated with a cryopreserved control population1. Journal of Animal Science. 90(10):3392-3397. https://doi.org/10.2527/jas.2011-4837S33923397901

Ceramide launches an acute anti-adhesion pro-migration cell signaling program in response to chemotherapy

Chemotherapy has been reported to upregulate sphingomylinases and increase cellular ceramide, often linked to the induction to cell death. In this work, we show that sublethal doses of doxorubicin and vorinostat still increased cellular ceramide, which was located predominantly at the plasma membrane. To interrogate possible functions of this specific pool of ceramide, we used recombinant enzymes to mimic physiological levels of ceramide at the plasma membrane upon chemotherapy treatment. Using mass spectrometry and network analysis, followed by experimental confirmation, the results revealed that this pool of ceramide acutely regulates cell adhesion and cell migration pathways with weak connections to commonly established ceramide functions (eg, cell death). Neutral sphingomyelinase 2 (nSMase2) was identified as responsible for the generation of plasma membrane ceramide upon chemotherapy treatment, and both ceramide at the plasma membrane and nSMase2 were necessary and sufficient to mediate these “side” effects of chemotherapy on cell adhesion and migration. This is the first time a specific pool of ceramide is interrogated for acute signaling functions, and the results define plasma membrane ceramide as an acute signaling effector necessary and sufficient for regulation of cell adhesion and cell migration under chemotherapeutical stress.Fil: Canals, Daniel. Stony Brook University; State University of New York;Fil: Salamone, Silvia. Stony Brook University; State University of New York;Fil: Santacreu, Bruno Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Nemeth, Erika. Stony Brook University; State University of New York;Fil: Aguilar, Daniel. Biomedical Research Networking Center in Hepatic and Digestive Diseases; EspañaFil: Hernandez Corbacho, María José. Stony Brook University; State University of New York;Fil: Adada, Mohamad. Stony Brook University; State University of New York;Fil: Staquicini, Daniela I.. Rutgers Cancer Institute of New Jersey; Estados UnidosFil: Arap, Wadih. Rutgers Cancer Institute of New Jersey; Estados UnidosFil: Pasqualini, Renata. Rutgers Cancer Institute of New Jersey; Estados UnidosFil: Haley, John. Stony Brook University; State University of New York;Fil: Obeid, Lina M.. Stony Brook University; State University of New York;Fil: Hannun, Yusuf A.. Stony Brook University; State University of New York

Ceramide launches an acute anti-adhesion pro-migration cell signaling program in response to chemotherapy

Chemotherapy has been reported to upregulate sphingomylinases and increase cellular ceramide, often linked to the induction to cell death. In this work, we show that sublethal doses of doxorubicin and vorinostat still increased cellular ceramide, which was located predominantly at the plasma membrane. To interrogate possible functions of this specific pool of ceramide, we used recombinant enzymes to mimic physiological levels of ceramide at the plasma membrane upon chemotherapy treatment. Using mass spectrometry and network analysis, followed by experimental confirmation, the results revealed that this pool of ceramide acutely regulates cell adhesion and cell migration pathways with weak connections to commonly established ceramide functions (eg, cell death). Neutral sphingomyelinase 2 (nSMase2) was identified as responsible for the generation of plasma membrane ceramide upon chemotherapy treatment, and both ceramide at the plasma membrane and nSMase2 were necessary and sufficient to mediate these “side” effects of chemotherapy on cell adhesion and migration. This is the first time a specific pool of ceramide is interrogated for acute signaling functions, and the results define plasma membrane ceramide as an acute signaling effector necessary and sufficient for regulation of cell adhesion and cell migration under chemotherapeutical stress.Fil: Canals, Daniel. Stony Brook University; State University of New York;Fil: Salamone, Silvia. Stony Brook University; State University of New York;Fil: Santacreu, Bruno Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Nemeth, Erika. Stony Brook University; State University of New York;Fil: Aguilar, Daniel. Biomedical Research Networking Center in Hepatic and Digestive Diseases; EspañaFil: Hernandez Corbacho, María José. Stony Brook University; State University of New York;Fil: Adada, Mohamad. Stony Brook University; State University of New York;Fil: Staquicini, Daniela I.. Rutgers Cancer Institute of New Jersey; Estados UnidosFil: Arap, Wadih. Rutgers Cancer Institute of New Jersey; Estados UnidosFil: Pasqualini, Renata. Rutgers Cancer Institute of New Jersey; Estados UnidosFil: Haley, John. Stony Brook University; State University of New York;Fil: Obeid, Lina M.. Stony Brook University; State University of New York;Fil: Hannun, Yusuf A.. Stony Brook University; State University of New York

TDP-43 regulates LC3ylation in neural tissue through ATG4B cryptic splicing inhibition

Amyotrophic lateral sclerosis (ALS) is an adult-onset motor neuron disease with a mean survival time of three years. The 97% of the cases have TDP-43 nuclear depletion and cytoplasmic aggregation in motor neurons. TDP-43 prevents non-conserved cryptic exon splicing in certain genes, maintaining transcript stability, including ATG4B, which is crucial for autophagosome maturation and Microtubule-associated proteins 1A/1B light chain 3B (LC3B) homeostasis. In ALS mice (G93A), Atg4b depletion worsens survival rates and autophagy function. For the first time, we observed an elevation of LC3ylation in the CNS of both ALS patients and atg4b−/− mouse spinal cords. Furthermore, LC3ylation modulates the distribution of ATG3 across membrane compartments. Antisense oligonucleotides (ASOs) targeting cryptic exon restore ATG4B mRNA in TARDBP knockdown cells. We further developed multi-target ASOs targeting TDP-43 binding sequences for a broader effect. Importantly, our ASO based in peptide-PMO conjugates show brain distribution post-IV administration, offering a non-invasive ASO-based treatment avenue for neurodegenerative diseases

Match-action: the role of motion and audio in creating global change blindness in film

An everyday example of change blindness is our difficulty to detect cuts in an edited moving-image. Edit Blindness (Smith & Henderson, 2008) is created by adhering to the continuity editing conventions of Hollywood, e.g. coinciding a cut with a sudden onset of motion (Match-Action). In this study we isolated the roles motion and audio play in limiting awareness of match-action cuts by removing motion before and/or after cuts in existing Hollywood film clips and presenting the clips with or without the original soundtrack whilst participants tried to detect cuts. Removing post-cut motion significantly decreased cut detection time and the probability of missing the cut. By comparison, removing pre-cut motion had no effect suggesting, contrary to the editing literature, that the onset of motion before a cut may not be as critical for creating edit blindness as the motion after a cut. Analysis of eye movements indicated that viewers reoriented less to new content across intact match-action cuts than shots with motion removed. Audio played a surprisingly large part in creating edit blindness with edit blindness mostly disappearing without audio. These results extend film editor intuitions and are discussed in the context of the Attentional Theory of Cinematic Continuity (Smith, 2012a)

Genetic selection for ovulation rate and litter size in rabbits: estimation of genetic parameters and direct and correlated responses

The aim of this work was to estimate direct and correlated responses in survival rates in an experiment of selection for ovulation rate (OR) and litter size (LS) in a line of rabbits (OR_LS). From generation 0 to 6 (first selection period), females were selected only for second gestation OR estimated by laparoscopy. From generation 7 to 13 (second selection period), a 2-stage selection for OR and LS was performed. In stage 1, females having the greatest OR at second gestation were selected. In stage 2, selection was for the greatest average LS of the first 2 parities of the females selected in stage 1. Total selection pressure in females was about 30%. The line had approximately 17 males and 75 females per generation. Traits recorded were OR estimated as the number of corpora lutea in both ovaries, number of implanted embryos (IE) estimated as the number of implantation sites, LS estimated as total number of rabbits born recorded at each parity, embryo survival (ES) estimated as IE/OR, fetal survival (FS) estimated as LS/IE, and prenatal survival (PS) estimated as LS/OR. Data were analyzed using Bayesian methodology. The estimated heritabilities of LS, OR, IE, ES, FS, and PS were 0.07, 0.21, 0.10, 0.07, 0.12, and 0.16, respectively. Direct and correlated responses from this study were estimated in each period of selection as the difference between the average genetic values of last and first generation. In the first selection period, OR increased 1.36 ova, but no correlated response was observed in LS due to a decrease on FS. Correlated responses for IE, ES, FS, and PS in the first selection period were 1.11, 0.00, -0.04, and -0.01, respectively. After 7 generations of 2-stage selection for OR and LS, OR increased 1.0 ova and response in LS was 0.9 kits. Correlated responses for IE, ES, FS, and PS in the second selection period were 1.14, 0.02, 0.02, and 0.07, respectively. Two-stage selection for OR and LS can be a promising procedure to improve LS in rabbits.This study was supported by the Comision Interministerial de Ciencia y Tecnologia CICYT-AGL2005-07624-C03-01 CICYT-AGL2008-05514-C02-01 and by funds from Generalitat Valenciana research programme (Prometeo 2009/125).Ziadi, C.; Mocé Cervera, ML.; Laborda Vidal, P.; Blasco Mateu, A.; Santacreu Jerez, MA. (2013). Genetic selection for ovulation rate and litter size in rabbits: estimation of genetic parameters and direct and correlated responses. Journal of Animal Science. 91(7):3113-3120. https://doi.org/10.2527/jas.2012-6043S3113312091

Transcriptome Kinetics Is Governed by a Genome-Wide Coupling of mRNA Production and Degradation: A Role for RNA Pol II

Transcriptome dynamics is governed by two opposing processes, mRNA production and degradation. Recent studies found that changes in these processes are frequently coordinated and that the relationship between them shapes transcriptome kinetics. Specifically, when transcription changes are counter-acted with changes in mRNA stability, transient fast-relaxing transcriptome kinetics is observed. A possible molecular mechanism underlying such coordinated regulation might lay in two RNA polymerase (Pol II) subunits, Rpb4 and Rpb7, which are recruited to mRNAs during transcription and later affect their degradation in the cytoplasm. Here we used a yeast strain carrying a mutant Pol II which poorly recruits these subunits. We show that this mutant strain is impaired in its ability to modulate mRNA stability in response to stress. The normal negative coordinated regulation is lost in the mutant, resulting in abnormal transcriptome profiles both with respect to magnitude and kinetics of responses. These results reveal an important role for Pol II, in regulation of both mRNA synthesis and degradation, and also in coordinating between them. We propose a simple model for production-degradation coupling that accounts for our observations. The model shows how a simple manipulation of the rates of co-transcriptional mRNA imprinting by Pol II may govern genome-wide transcriptome kinetics in response to environmental changes