ix, 1055 s. : il., tab. ; 27 cm
- MeSH
- Genetic Diseases, Inborn genetics MeSH
- Genetics, Medical MeSH
- Growth and Development genetics MeSH
- Developmental Biology MeSH
- Gene Expression Regulation, Developmental MeSH
- Publication type
- Monograph MeSH
- Conspectus
- Obecná genetika. Obecná cytogenetika. Evoluce
- NML Fields
- genetika, lékařská genetika
BACKGROUND: Comparative transcriptomics can answer many questions in developmental and evolutionary developmental biology. Most transcriptomic studies start by showing global patterns of variation in transcriptomes that differ between species or organs through developmental time. However, little is known about the kinds of expression differences that shape these patterns. RESULTS: We compared transcriptomes during the development of two morphologically distinct serial organs, the upper and lower first molars of the mouse. We found that these two types of teeth largely share the same gene expression dynamics but that three major transcriptomic signatures distinguish them, all of which are shaped by differences in the relative abundance of different cell types. First, lower/upper molar differences are maintained throughout morphogenesis and stem from differences in the relative abundance of mesenchyme and from constant differences in gene expression within tissues. Second, there are clear time-shift differences in the transcriptomes of the two molars related to cusp tissue abundance. Third, the transcriptomes differ most during early-mid crown morphogenesis, corresponding to exaggerated morphogenetic processes in the upper molar involving fewer mitotic cells but more migrating cells. From these findings, we formulate hypotheses about the mechanisms enabling the two molars to reach different phenotypes. We also successfully applied our approach to forelimb and hindlimb development. CONCLUSIONS: Gene expression in a complex tissue reflects not only transcriptional regulation but also abundance of different cell types. This knowledge provides valuable insights into the cellular processes underpinning differences in organ development. Our approach should be applicable to most comparative developmental contexts.
- MeSH
- Epithelium embryology metabolism MeSH
- Mesoderm embryology metabolism MeSH
- Molar embryology metabolism MeSH
- Morphogenesis genetics MeSH
- Mosaicism MeSH
- Mice MeSH
- Organogenesis genetics MeSH
- Signal Transduction MeSH
- Transcriptome * MeSH
- Developmental Biology * methods MeSH
- Gene Expression Regulation, Developmental * MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- MeSH
- Hypothalamus MeSH
- Rats MeSH
- Thyrotropin secretion MeSH
- Developmental Biology MeSH
- Check Tag
- Rats MeSH
Hypertension is one of the major risk factor of cardiovascular diseases, but after a century of clinical and basic research, the discrete etiology of this disease is still not fully understood. One reason is that blood pressure is a quantitative trait with multifactorial determination. Numerous genes, environmental factors as well as epigenetic factors should be considered. There is no doubt that although the full manifestation of hypertension and other cardiovascular diseases usually occurs predominantly in adulthood and/or senescence, the roots can be traced back to early ontogeny. The detailed knowledge of the ontogenetic changes occurring in the cardiovascular system of experimental animals during particular critical periods (developmental windows) could help to solve this problem in humans and might facilitate the age-specific prevention of human hypertension. We thus believe that this approach might contribute to the reduction of cardiovascular morbidity among susceptible individuals in the future.
- MeSH
- Arterial Pressure genetics MeSH
- Epistasis, Genetic MeSH
- Hypertension genetics pathology prevention & control MeSH
- Cardiovascular Diseases etiology genetics MeSH
- Blood Pressure genetics MeSH
- Humans MeSH
- Quantitative Trait Loci MeSH
- Risk Factors MeSH
- Gene Expression Regulation, Developmental MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
Being sessile organisms, plants have evolved mechanisms allowing them to control their growth and development in response to environmental changes. This occurs by means of complex interacting signalling networks that integrate diverse environmental cues into co-ordinated and highly regulated responses. Auxin is an essential phytohormone that functions as a signalling molecule, driving both growth and developmental processes. It is involved in numerous biological processes ranging from control of cell expansion and cell division to tissue specification, embryogenesis, and organ development. All these processes require the formation of auxin gradients established and maintained through the combined processes of biosynthesis, metabolism, and inter- and intracellular directional transport. Environmental conditions can profoundly affect the plant developmental programme, and the co-ordinated shoot and root growth ought to be fine-tuned to environmental challenges such as temperature, light, and nutrient and water content. The key role of auxin as an integrator of environmental signals has become clear in recent years, and emerging evidence implicates auxin biosynthesis as an essential component of the overall mechanisms of plants tolerance to stress. In this review, we provide an account of auxin's role as an integrator of environmental signals and, in particular, we highlight the effect of these signals on the control of auxin production.
The circadian rhythms of mammals are generated by the circadian clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus. Its intrinsic period is entrained to a 24 h cycle by external cues, mainly by light. Light impinging on the SCN at night causes either advancing or delaying phase shifts of the circadian clock. N-methyl-d-aspartate receptors (NMDAR) are the main glutamate receptors mediating the effect of light on the molecular clockwork in the SCN. They are composed of multiple subunits, each with specific characteristics whose mutual interactions strongly determine properties of the receptor. In the brain, the distribution of NMDAR subunits depends on the region and developmental stage. Here, we report the circadian expression of the NMDAR1 subunit in the adult rat SCN and depict its splice variants that may constitute the functional receptor channel in the SCN. During ontogenesis, expression of two of the NMDAR1 subunit splice variants, as well as the NMDAR3A and 3B subunits, exhibits developmental loss around the time of eye opening. Moreover, we demonstrate the spatial and developmental characteristics of the expression of the truncated splice form of NMDAR1 subunit NR1-E in the brain. Our data suggest that specific properties of the NMDAR subunits we describe within the SCN likely influence the photic transduction pathways mediating the clock entrainment. Furthermore, the developmental changes in NMDAR composition may contribute to the gradual postnatal maturation of the entrainment pathways.
- MeSH
- Analysis of Variance MeSH
- Circadian Rhythm physiology MeSH
- Embryo, Mammalian MeSH
- Financing, Organized MeSH
- Rats MeSH
- RNA, Messenger metabolism MeSH
- Animals, Newborn MeSH
- Suprachiasmatic Nucleus physiology MeSH
- Rats, Wistar MeSH
- Protein Isoforms genetics metabolism MeSH
- Receptors, N-Methyl-D-Aspartate genetics metabolism MeSH
- Gene Expression Regulation, Developmental physiology MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
The developmental competence of oocytes is acquired progressively during folliculogenesis and is linked to follicular size. It has been documented that oocytes originating from larger follicles exhibit a greater ability to develop to the blastocyst stage. The differences in cytoplasmic factors such as mRNA transcripts could explain the differences in oocyte developmental potential. We used bovine oligonucleotide microarrays to characterize differences between the gene expression profiles of germinal vesicle stage (GV) oocytes with greater developmental competence from medium follicles (MF) and those with less developmental competence from small follicles (SF). After normalizing the microarray data, our analysis found differences in the level of 60 transcripts (≥1.4 fold), corresponding to 49 upregulated and 11 downregulated transcripts in MF oocytes compared to SF oocytes. The gene expression data were classified according to gene ontology, the majority of the genes were associated with the regulation of transcription, translation, the cell cycle, and mitochondrial activity. A subset of 16 selected genes was validated for GV oocytes by quantitative real-time RT-PCR; significant differences (P˂0.01) were found in the level of TAF1A, MTRF1L, ATP5C1, UBL5 and MAP3K13 between the MF and SF oocytes. After maturation the transcript level remained stable for ATP5F1, BRD7, and UBL5 in both oocyte categories. The transcript level of another 13 genes substantially dropped in the MF and/or SF oocytes. It can be concluded that the developmental competence of bovine oocytes and embryos may be a quantitative trait dependent on small changes in the transcription profiles of many genes.
- MeSH
- Embryonic Development genetics MeSH
- Fertilization in Vitro MeSH
- Oocytes metabolism physiology MeSH
- Oogenesis genetics MeSH
- Ovarian Follicle metabolism MeSH
- Oligonucleotide Array Sequence Analysis MeSH
- Cattle genetics physiology MeSH
- Gene Expression Profiling MeSH
- Gene Expression Regulation, Developmental MeSH
- Animals MeSH
- Check Tag
- Cattle genetics physiology MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Although improvements in culture system have enhanced in vitro embryo production, success rates are still not adequate. The reasons for developmental arrest of a part of in vitro produced embryos are unknown, but are connected in part with low cytoplasmic competence of oocytes. The immaturity of cytoplasm can negatively influence fertilization efficiency and subsequent progression through embryonic genome activation (EGA), which are necessary steps in further pre-implantation development. A large number of studies have compared mRNA abundance among oocytes with different developmental competence with the aim to find markers of the normal embryo development. The amount of mitochondrial DNA (mtDNA) and mRNA for mitochondrial transcriptional factors directing oxidative phosphorylation belongs to such promising markers. Nevertheless, recently published studies revealed that the mammalian embryo is able to compensate for a reduced level of mtDNA in oocyte during subsequent pre-implantation development. The search for other molecular markers is in progress. Characterization of oocyte and embryonic mRNA expression patterns during the pre-implantation period, and their relationship to the successful in vitro and in vivo development will be essential for defining the optimized culture conditions or the nuclear transfer protocols. Microarrays technology enables us to reveal the differentially expressed genes during EGA, and to compare the expression profile of in vivo and in vitro produced embryos. Recent evidence indicates that the depletion of the pool of stored maternal mRNAs is critical for subsequent embryo development. All these experiments gradually offer a list of possible candidates for quality and developmental competence markers for mammalian oocytes and pre-implantation embryos.
- MeSH
- Transcription, Genetic * MeSH
- RNA, Messenger genetics metabolism MeSH
- Oocytes metabolism MeSH
- Cattle embryology MeSH
- Transcriptome * MeSH
- Gene Expression Regulation, Developmental physiology MeSH
- Animals MeSH
- Check Tag
- Cattle embryology MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- MeSH
- Apraxias diagnosis MeSH
- Cerebrovascular Disorders MeSH
- Adult MeSH
- Attention Deficit Disorder with Hyperactivity MeSH
- Kinesics MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Personality Disorders MeSH
- Psychomotor Disorders MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
