The Importance of Sorting Calcium in Plant Cells: Uncovering the Roles of A Sarcoplasmic/Endoplasmic Reticulum-Like Calcium ATPase

The spatial and temporal dynamics of intracellular Ca2+ in response to environmental and hormonal cues underscore the importance of Ca2+ transport during plant growth and development. The Arabidopsis thaliana genome predicts multiple genes encoding Ca2+ transporters, though the biological roles of most are unknown. Here I determine the function of AtECA3 which represents the first plant P-type 2A ATPase resembling mammalian sarcoplasmic/endoplasmic reticulum Ca ATPase (SERCA). AtECA3 (At1g10130) expressed in a yeast mutant lacking its endogenous Ca2+ pumps functionally substitutes for the defective Ca2+-ATPases. AtECA3-dependent yeast growth is blocked by thapsigargin, a specific SERCA inhibitor. The results suggest that AtECA3 is a cation pump with specificity for Ca2+ and Mn2+, and that AtECA3 enhances yeast growth on Ca2+-depleted medium or on medium with high Mn2+ by sequestrating Ca2+ or Mn2+, respectively, into endomembrane compartments. AtECA3 is expressed in pollen grains as revealed by promoter::GUS analyses and a green fluorescence protein (GFP)-tagged to AtECA3 labels endomembranes at the pollen tip. In vitro tube growth of wild-type pollen is enhanced by 10 mM Ca2+, and inhibited by thapsigargin, suggesting that AtECA3 supports tube elongation by sorting intracellular Ca2+ to appropriate compartments. This idea is supported by genetic evidence, where three T-DNA insertional mutants show 33% reduction in pollen tube length. This defect lowers sperm transmission shown as segregation distortion and decreased seed set. AtECA3 is also expressed in vascular tissues of young roots and leaves, and the GFP-tagged protein colocalizes with two Golgi markers. Three millimolar Ca2+ stimulate root growth of wild-type but not of mutants, indicating that Ca2+ accumulation in Golgi lumen is critical for growth. Root growth of eca3-4, but not of wild-type, is hypersensitive to 50 μM Mn2+. Thus loading Mn2+ into Golgi lumen by AtECA3 supports root growth. Intriguingly, mutant roots show 80% increase in apoplastic peroxidase suggesting that secretory activities became deregulated. In conclusion, I provide molecular evidence for a Golgi Ca2+/Mn2+ pump in plants. Ca2+ and Mn2+ accumulation into Golgi/secretory compartments by AtECA3 and perhaps cation release from these stores affect secretory activities critical for root growth, pollen tube elongation and male fertility

Training of Working Memory Impacts Neural Processing of Vocal Pitch Regulation

Working memory training can improve the performance of tasks that were not trained. Whether auditory-motor integration for voice control can benefit from working memory training, however, remains unclear. The present event-related potential (ERP) study examined the impact of working memory training on the auditory-motor processing of vocal pitch. Trained participants underwent adaptive working memory training using a digit span backwards paradigm, while control participants did not receive any training. Before and after training, both trained and control participants were exposed to frequency-altered auditory feedback while producing vocalizations. After training, trained participants exhibited significantly decreased N1 amplitudes and increased P2 amplitudes in response to pitch errors in voice auditory feedback. In addition, there was a significant positive correlation between the degree of improvement in working memory capacity and the post-pre difference in P2 amplitudes. Training-related changes in the vocal compensation, however, were not observed. There was no systematic change in either vocal or cortical responses for control participants. These findings provide evidence that working memory training impacts the cortical processing of feedback errors in vocal pitch regulation. This enhanced cortical processing may be the result of increased neural efficiency in the detection of pitch errors between the intended and actual feedback

Temporal Lobe Epilepsy Alters Auditory-motor Integration For Voice Control

Temporal lobe epilepsy (TLE) is the most common drug-refractory focal epilepsy in adults. Previous research has shown that patients with TLE exhibit decreased performance in listening to speech sounds and deficits in the cortical processing of auditory information. Whether TLE compromises auditory-motor integration for voice control, however, remains largely unknown. To address this question, event-related potentials (ERPs) and vocal responses to vocal pitch errors (1/2 or 2 semitones upward) heard in auditory feedback were compared across 28 patients with TLE and 28 healthy controls. Patients with TLE produced significantly larger vocal responses but smaller P2 responses than healthy controls. Moreover, patients with TLE exhibited a positive correlation between vocal response magnitude and baseline voice variability and a negative correlation between P2 amplitude and disease duration. Graphical network analyses revealed a disrupted neuronal network for patients with TLE with a significant increase of clustering coefficients and path lengths as compared to healthy controls. These findings provide strong evidence that TLE is associated with an atypical integration of the auditory and motor systems for vocal pitch regulation, and that the functional networks that support the auditory-motor processing of pitch feedback errors differ between patients with TLE and healthy controls

Penerapan Pendekatan Pengajaran Terbalik (Reciprocal Teaching) Untuk Meningkatkan Kemandirian Belajar Biologi Siswa Kelas Vii-g SMP N 5 Karanganyar Tahun Pelajaran 2010/ 2011

– The objective of this study is to improve student independence in learning biology by implementing Inverted Teaching Approach (Reciprocal Teaching) on Environmental Management material. This research is a classroom action research. This research was conducted in two cycles. Each cycle consisted of planning, implementation of the action,observation, and reflection. The subjects of the study were VII-G class students of SMP Negeri 5 Karanganyar in the academic year of 2010/2011. The number of the students was 32. The technique and instrumen of collectiing data were questionnaire, observation, and interviews. The technique of analyzing data was descriptive analysis techniques. Triangulation technique was used in data validation. The results proved that by implementing Inverted Teaching Approach (Reciprocal Teaching) students\u27 independence in learning biology enhanced. It is based on the results of questionnaires, observations and interviews. The questionnaire of students\u27 learning independence showed that the mean percentage of students\u27 achievement in each indicator in pre-cycle, cycle I, and cycle II was 67.97%, 72.55%, and 77.58% respectively. The observation of students\u27 learning independence showed that the mean percentage of students\u27 achievement in each indicator in pre-cycle, cycle I, and cycle II was 39.68%, 67.5%, and 80.62% respectively. It can be concluded that the implementation of Inverted Teaching Approach (Reciprocal Teaching) can enhance students learning independence

Simulation of CSSTs astrometric capability

The China Space Station Telescope (CSST) will enter a low Earth orbit around 2024 and operate for 10 years, with seven of those years devoted to surveying the area of the median-to-high Galactic latitude and median-to-high Ecliptic latitude of the sky. To maximize the scientific output of CSST, it is important to optimize the survey schedule. We aim to evaluate the astrometric capability of CSST for a given survey schedule and to provide independent suggestions for the optimization of the survey strategy. For this purpose, we first construct the astrometric model and then conduct simulated observations based on the given survey schedule. The astrometric solution is obtained by analyzing the simulated observation data. And then we evaluate the astrometric capability of CSST by analyzing the properties of the astrometric solution. We find that the accuracy of parallax and proper motion of CSST is better than 1 mas( yr1) for the sources of 18-22 mag in g band, and about 1-10 mas( yr1) for the sources of 22-26 mag in g band, respectively. The results from real survey could be worse since the assumptions are optimistic and simple. We find that optimizing the survey schedule can improve the astrometric accuracy of CSST. In the future, we will improve the astrometric capability of CSST by continuously iterating and optimizing the survey schedule.Comment: 17 pages, 10 figure

Training of Working Memory Impacts Neural Processing of Vocal Pitch Regulation

Working memory training can improve the performance of tasks that were not trained. Whether auditory-motor integration for voice control can benefit from working memory training, however, remains unclear. The present event-related potential (ERP) study examined the impact of working memory training on the auditory-motor processing of vocal pitch. Trained participants underwent adaptive working memory training using a digit span backwards paradigm, while control participants did not receive any training. Before and after training, both trained and control participants were exposed to frequency-altered auditory feedback while producing vocalizations. After training, trained participants exhibited significantly decreased N1 amplitudes and increased P2 amplitudes in response to pitch errors in voice auditory feedback. In addition, there was a significant positive correlation between the degree of improvement in working memory capacity and the post-pre difference in P2 amplitudes. Training-related changes in the vocal compensation, however, were not observed. There was no systematic change in either vocal or cortical responses for control participants. These findings provide evidence that working memory training impacts the cortical processing of feedback errors in vocal pitch regulation. This enhanced cortical processing may be the result of increased neural efficiency in the detection of pitch errors between the intended and actual feedback