Background And Aims: Ranunculaceae has a prominent phylogenetic position in Ranunculales which appears at the base of eudicots. The aims of the present paper are to reveal the features of ovule morphogenesis in different taxa and gain a better understanding of the systematics of Ranunculaceae.
Methods: Flowers of 17 species from three subfamilies, nine tribes and 16 genera of Ranunculaceae, at successive developmental stages, were collected in the wild and studied with a scanning electron microscope.
Key Results: The integuments in the unitegmic ovules in Helleborus, Ranunculus and Oxygraphis, as well as the inner integuments in the bitegmic genera, initiate annularly and eventually become cup-shaped. However, the integuments in the unitegmic ovules in Anemone and Clematis, as well as the outer integuments in the bitegmic genera, arise semi-annularly and eventually become hood-shaped. Different kinds of appendages appear on the ovules during development. In Coptis of subfamily Coptidoideae, a wrap-shaped appendage arises outside the ovule and envelopes the ovule entirely. In the genera of subfamily Thalictroideae and tribe Anemoneae of subfamily Ranunculoideae, appendages appear on the placenta, the funicle or both. In tribe Helleboreae of subfamily Ranunculoideae, an alary appendage is initiated where the integument and the funicle join and becomes hood-shaped.
Conclusions: Ovule morphogenesis characteristics are significant in classification at the levels of subfamilies and tribes. The initiation patterns of the integuments and the development of appendages show diversity in Ranunculaceae. The present observations suggest that the bitegmic, hood-shaped outer integument and endostomic micropyle are primitive while the unitegmic, cupular-shaped outer integument and bistomic micropyle are derivative.
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http://dx.doi.org/10.1093/aob/mcm298 | DOI Listing |
Genes (Basel)
January 2025
National Key Laboratory for Tropical Crop Breeding, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China.
Flowers, serving as the reproductive structures of angiosperms, perform an integral role in plant biology and are fundamental to understanding plant evolution and taxonomy. The growth and organogenesis of flowers are driven by numerous factors, such as external environmental conditions and internal physiological processes, resulting in diverse traits across species or even within the same species. Among these factors, genes play a central role, governing the entire developmental process.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; CAU-SC Advanced Agricultural & Industrial institute, CAU-SCCD Advanced Agricultural & Industrial institute, China Agricultural University, Chengdu 611430, China. Electronic address:
Litter size in pigs is affected by factors such as ovulation number, embryonic survival, and uterine environment conditions. Endometrial epithelial and stromal cells represent the first site of contact between the embryo and sows; therefore, dynamic changes in the growth and development of these cells are among the major factors affecting the intrauterine environment and implantation. Bone morphogenetic protein receptor type-1B (BMPR1B) is a receptor of the bone morphogenetic protein (BMP) family that has been identified as a candidate gene for reproductive traits in pigs.
View Article and Find Full Text PDFBiophys Rev
October 2024
Mechanobiology Institute, National University of Singapore, Singapore, Singapore.
A key developmental stage in mammalian folliculogenesis is the formation of a fluid-filled lumen (antrum) prior to ovulation. While it has long been speculated that the follicular fluid is essential for oocyte maturation and ovulation, little is known about the morphogenesis and the mechanisms driving the antrum formation and ovulation, potentially due to challenges in imaging tissue dynamics in large tissues. Misregulation of such processes leads to anovulation, a hallmark of infertility in ageing and diseases such as the polycystic ovary syndrome (PCOS).
View Article and Find Full Text PDFPlant J
January 2025
Escola Superior de Agricultura "Luiz de Queiroz" (ESALQ), Universidade de São Paulo, 13418-900 Piracicaba, São Paulo, Brazil.
Fruit morphogenesis is determined by the coordination of cell division and expansion, which are fundamental processes required for the development of all plant organs. Here, we show that the regulation of TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) LANCEOLATE (TCP2/LA) by miR319 is crucial for tomato fruit morphology. The loss of miR319 regulation in the semi-dominant La mutant led to a premature SlTCP2/LA expression during gynoecium patterning, which results in modified cell division during carpel development.
View Article and Find Full Text PDFHum Reprod
January 2025
Education Program in Reproduction and Development, EPRD, Department of obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia.
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