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Sieve elements (SEs) degrade selected organelles and cytoplasmic structures when they differentiate. According to classical investigations, only smooth ER, mitochondria, sieve element plastids, and, in most cases, P-proteins remain in mature SEs. More recent proteomics and immuno-histochemical studies, however, suggested that additional components including a protein-synthesizing machinery and a fully developed actin cytoskeleton operate in mature SEs. These interpretations are at odds with conventional imaging studies. Here we discuss potential causes for these discrepancies, concluding that differentiating SEs may play a role by 'contaminating' phloem exudates.
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http://dx.doi.org/10.1016/j.pbi.2017.12.008 | DOI Listing |
Plant Physiol Biochem
July 2025
INRAE, ONF, BioForA, UMR, 0588, F-45075, Orléans, France.
It is assumed that the production of somatic embryos (SEs), which closely resemble fully mature zygotic embryos (ZEs), increases the chance of producing somatic plants equivalent to seedlings. Desiccation is crucial to reduce the water content of SEs and to initiate biochemical changes that support germination and conversion into plants. We investigated the biological, histological, biochemical and molecular changes in the SEs of hybrid larch Larix eurolepis exposed to desiccation at high relative humidity (RH; 98 %), reduced RH (59 %), or a combination of both.
View Article and Find Full Text PDFChild Dev
July 2025
Erasmus School of Social and Behavioral Sciences, Erasmus University Rotterdam, Rotterdam, the Netherlands.
This study examines the distinct developmental trajectories of prosocial and rebellious behaviors in adolescence. Using data from an accelerated three-wave project (2018-2022) among adolescents aged 9-22 years (N = 142, 63% female, middle-high SES, white European descent), trajectories of prosocial actions toward friends and peers, prosocial tendencies across multiple situations, giving to charities, and general social value orientation were examined. By examining age-, puberty-, and hormonal-related trajectories, the study demonstrates increases in prosocial behaviors to friends and peers, dire and compliant behavior, and charitable giving, which were more strongly explained by pubertal maturation than age.
View Article and Find Full Text PDFAnn Hum Biol
December 2025
School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK.
Background: Studying the extent to which delayed skeletal maturation may contribute to childhood height deficits is important for assessing potential for recovery in heights.
Aim: To investigate the discrepancy in height-for-age Z-scores (HAZ) based on chronological age (HAZ-CA) compared to bone age (HAZ-BA) and estimate proportion of HAZ deficits attributable to delayed maturation in both sexes.
Subjects And Methods: Using the WHO Growth References, HAZ-CA and HAZ-BA were calculated for Guatemala City children aged 6-8.
Int J Biol Macromol
June 2025
Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization, Sichuan Province and Ministry of Education, Southwest Minzu University, Chengdu, China. Electronic address:
Intramuscular fat (IMF) content is a crucial factor in determining meat quality, yet yak meat is typically characterized by low IMF levels. The epigenetic mechanisms underlying IMF deposition, particularly the role of super-enhancers (SEs), remain poorly understood. RNA-seq identified 66 differentially expressed (DE) miRNAs and 56 DE pri-miRNAs in yak longissimus dorsi with varying IMF contents.
View Article and Find Full Text PDFBMC Plant Biol
April 2025
Department of General Botany, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznanskiego 6, Poznan, 61-614, Poland.
Phloem, an exceptional plant vascular tissue, facilitates the transport of photoassimilates, RNAs, and other signaling substances from the leaves to the roots throughout the plant. Among the specialized phloem cells are the conductive sieve elements (SEs), which are unique in that they remain alive despite lacking several cell organelles, including the nucleus, plastids, and most mitochondria. These SEs contain a specific proteinaceous structure composed of phloem-specific proteins (P-proteins), whose function is not yet fully understood.
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