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Cerda, J.

Publications and source records attributed to Cerda, J..

6 recordsLinked to original sources

Cell type diversification and phenotype convergence underlying white fin-ornamentation of cyprinid fishes

Neural crest derived cells offer valuable opportunities to dissect mechanisms of cell fate specification and differentiation within individual ontogenies and the underpinnings of cell type diversification over evolutionary time. Particularly useful for such analyses are pigment cells of ectothermic vertebrates that arise from neural crest cells, or via latent neural crest derived stem cells, and comprise several classes with cell-type specific pigmentary phenotypes. Among these are white cells, "leucophores," present in a variety of species that contribute to patterns on the body or ornamentation on the fins. To better understand developmental and evolutionary origins of these cells we have examined leucophores harboring deposits of yellow/orange carotenoids, "xantholeucophores," of zebrafish and leucophores of white cloud minnow, within the same family Cyprinidae. We show that white phenotypes of both cell types require sepiapterin reductase that promotes accumulation of pale and colorless pteridines. We further demonstrate that xantholeucophores develop directly from yellow sepiapterin rich xanthophore-like cells and that this transition requires both gap junctional activity and permeability of the aquaglyceroporin / peroxiporin channel Aquaporin 3. These findings identify these white cells as distinct developmentally, genetically, and biochemically from another type of white cell in zebrafish and other white cells present across phylogenetic lineages. Our results highlight remarkable convergences and parallelisms in the acquisition of white cell phenotypes within and between species and identify this as a rich system for enquiries into the evolutionary individuation of novel cell types. SignificanceUnderstanding how cell types arise is fundamental to explaining animal complexity. Pigment cells offer opportunities to address this question because they display striking variation. We show that white pigment cells comprise multiple classes with independent origins. In zebrafish, white cells on one fin develop from melanophores whereas white cells on another fin develop from yellow precursors that convert their pigments to colorless ones. White cells of a related minnow require the same colorless pigments yet differ in other ways. These findings illuminate remarkable convergence: white cells have arisen repeatedly from different progenitor cell lineages by different mechanisms. This diversity--even within and between closely related species--identifies a powerful model for understanding the evolution of cell types with distinct identities and functions.

developmental biology↗

Multisite Assembly of Gateway Induced Clones (MAGIC): a flexible cloning toolbox withdiverse applications in vertebrate model systems.

Here we present the Multisite Assembly of Gateway Induced Clones (MAGIC) system, which harnesses site-specific recombination-based cloning via Gateway technology for rapid, modular assembly of between 1 and 3 "Entry" vector components, all into a fourth, standard high copy "Destination" plasmid backbone. The MAGIC toolkit spans a range of in vitro and in vivo uses, from directing tunable gene expression, to driving simultaneous expression of microRNAs and fluorescent reporters, to enabling site-specific recombinase-dependent gene expression. All MAGIC system components are directly compatible with existing multisite gateway Tol2 systems currently used in zebrafish, as well as existing eukaryotic cell culture expression Destination plasmids, and available mammalian lentiviral and adenoviral Destination vectors, allowing rapid cross-species experimentation. Moreover, herein we describe novel vectors with flanking piggyBac transposon elements for stable genomic integration in vitro or in vivo when used with piggyBac transposase. Collectively, the MAGIC system facilitates transgenesis in cultured mammalian cells, electroporated mouse and chick embryos, as well as in injected zebrafish embryos, enabling the rapid generation of innovative DNA constructs for biological research due to a shared, common plasmid platform.

molecular biology↗

EZ Clear for simple, rapid, and robust mouse whole organ clearing

Tissue clearing for whole organ cell profiling has revolutionized biology and imaging for exploration of organs in three-dimensional space without compromising tissue architecture. But complicated, laborious procedures, or expensive equipment, as well as the use of hazardous, organic solvents prevents the widespread adoption of these methods. Here we report a simple and rapid tissue clearing method, EZ Clear, that can clear whole adult mouse organs in 48 hours in just three simple steps. Samples stay at room temperature and remain hydrated throughout the clearing process, preserving endogenous and synthetic fluorescence, without altering sample size. After wholemount clearing and imaging, EZ Cleared samples can be further processed for downstream embedding and cryosectioning followed by standard histology or immunostaining, without loss of endogenous or synthetic fluorescence signal. Overall, the simplicity, speed, and flexibility of EZ Clear make it easy to adopt and apply to diverse approaches in biomedical research.

developmental biology↗

Protamine lacking piscine spermatozoa are transcriptionally active

Transcriptional quiescence of post-meiotic spermatozoa associated with protamine-mediated chromatin condensation is widely recognized in animals. How sperm acquire the extratesticular maturational competence to move and fertilize the egg is therefore thought to occur via non-transcriptional mechanisms. Here, using transcriptional profiling during spermatozoon differentiation in a fish that does not condense chromatin with protamines, we uncover spatially distinct roles of the GnRH receptor and PDGF signaling pathways between the somatic epithelia of the extratesticular ducts and the maturing spermatozoa. In vitro induction and inhibition experiments demonstrate that the endocrine signaling pathways are conserved in different lineages of fish and activate de novo transcription of spermatozoon genes required for the acquisition of full motility. These experiments further confirmed that mitochondrial translation is important for sperm maturation in anamniotes as in amniotes, but that transcriptional quiescence of post-meiotic spermatozoa is not a pan vertebrate phenomenon. On the contrary, the data show that the identified signal transduction pathways between the soma and the sperm upregulate effector genes essential for maturational competence and male fertility.

cell biology↗

Providing recombinant gonadotropin-based therapies that induce complete gametogenesis and produce viable larvae from an immature teleost, flathead grey mullet (Mugil cephalus)

Under intensive captive conditions, wild-caught flathead grey mullet (Mugil cephalus) females remained arrested at early gonad development and no sperm could be obtained from males. With the aim to induce and complete oogenesis, induce the release of sperm and obtain fertilized eggs, adult female and male grey mullet were treated with M. cephalus single-chain recombinant gonadotropins (rGths), follicle-stimulating (rFsh) and luteinizing (rLh) hormones. In Experiment 1, fish were treated with a weekly dose of rFsh (15 g kg-1), which in females significantly (P < 0.001) increased plasma concentration of 17{beta}-estradiol and induced vitellogenic oocyte growth up to a maximum mean diameter of 425 {+/-} 19 m after 9 weeks of treatment. In Experiment 2, fish were treated with weekly injections of both rFsh and rLh at different doses (from 2.5 to 12 g kg-1). Oocyte diameter reached 609 {+/-} 5 m, from which final oocyte maturation and ovulation was induced with 30 g kg-1 of rLh and 40 mg kg-1 of progesterone. Good quality sperm (> 75% motile spermatozoa) was obtained from males in both experiments, and in Exp. 2 the addition of rLh induced the production of higher quantities of sperm that were used to fertilise the eggs. Although fertilisation was low (0.4 %), these fertilized eggs with embryo development produced viable larvae (71% hatching rate). This is the first report in a teleost species, to obtain larvae from eggs that were from immature females induced through to maturation with rGths. In comparison, control females remained arrested as immature fish and control males did not produce sperm. The study demonstrated that both rGths are effective to induce the entire process of oogenesis in sexually immature female grey mullet and to obtain flowing sperm from males, adding more data to confirm the roles of the Gths in teleost gametogenesis. This advance provides the bases of a therapy for the use in the aquaculture of teleost of commercial interest or the conservation of endangered species.

physiology↗

Single nucleotide variant at the alphaVbeta3 integrin associated to Andes virus infection susceptibility.

BackgroundANDV, agent of hantavirus cardiopulmonary syndrome, enters through integrin cell protein. A change from leucine-to-proline at residues 33 in the PSI-domain (L33P) inhibits ANDV recognition. We assessed the association between this human-variant and ANDV infection.\n\nResultsWe defined susceptible genotype to \"TT\" (coding leucine) and protective \"CC\" (coding proline). TT was in 89.2% (66/74) of a first cohort of ANDV-cases and in 60% (63/105) of exposed close-household contacts who remained unifected (p<0.05). Protective genotype was absent in all 85 ANDV cases in both cohorts and was present at 11.4% in exposed close-household contacts who remained uninfected. Logistic regression modeling to become a case had an OR 6.2-12.6 (p<0.05) in presence of TT and ANDV well-known risk activities. Moreover, OR of 7.3 was obtained when TT condition was analyzed for two groups exposed to the same environmental risk.\n\nConclusionHost genetic background has an important role in ANDV-infection susceptibility in the studied population.\n\nAuthor summaryHantavirus is a worldwide infection known to cause two different diseases: the hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS or HPS), diseases seen in the old world and new world hantaviruses, respectively. Andes orthohantavirus (ANDV), is the etiological agent of HCPS in Chile and South of Argentina, and is the only hantavirus recognized to be transmited person-to-person. It has been suggested that {beta}3-integrin is a cellular receptor for ANDV entry into cells. Here we try to understand the role of one human genetic variant of {beta}3-integrin in susceptibility to ANDV-infection. We compared, exposed infected and non infected subjects, and their genotype differences regarding a {beta}3 integrin variant that change a Leucine to Proline at PSI domain of the receptor. Leucine and proline aminoacids at the PSI domain, turn the cell susceptible or resistant to ANDV-infection, respectively. We were able to show genotype differences in cases and close-household contact that suggest differences in ANDV-infection susceptibility. Our results propose that the TT genotype, that codes to leucine, is a risk factor to become infected with ANDV, and the CC genotype that codes for proline at PSI domain, is a protective factor. (193/200)

microbiology↗