Abstract：
:Undifferentiated spermatogonia (Aund) or spermatogonial stem cells (SSCs) are committed to the establishment and maintenance of spermatogenesis and fertility throughout a male's life and are located in a highly specialized microenvironment called niche that regulates their fate. Although several studies have been developed on SSCs in mammalian testis, little is known about other vertebrate classes. The present study is the first to perform a more detailed investigation on the spermatogonial cells and their niche in a reptilian species. Thus, we characterized Aund/SSCs and evaluated the existence of SSCs niche in the Kinosternon scorpioides, a freshwater turtle found from Mexico to northern and central South America. Our results showed that, in this species, Aund/SSCs exhibited a nuclear morphological pattern similar to those described for other mammalian species already investigated. However, in comparison to other spermatogonial cell types, Aund/SSCs presented the largest nuclear volume in this turtle. Similar to some mammalian and fish species investigated, both GFRA1 and CSF1 receptors were expressed in Aund/SSCs in K. scorpioides. Also, as K. scorpioides Aund/SSCs were preferentially located near blood vessels, it can be suggested that this niche characteristic is a well conserved feature during evolution. Besides being valuable for comparative reproductive biology, our findings represent an important step towards the understanding of SSCs biology and the development of valuable systems/tools for SSCs culture and cryopreservation in turtles. Moreover, we expect that the above-mentioned results will be useful for reproductive biotechnologies as well as for governmental programs aiming at reptilian species conservation.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Costa GMJ,Sousa AL,Figueiredo AFA,Lacerda SMSN,França LRdoi
10.1016/j.ygcen.2018.06.019subject
Has Abstractpub_date
2019-03-01 00:00:00pages
163-171eissn
0016-6480issn
1095-6840pii
S0016-6480(18)30215-6journal_volume
273pub_type
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
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doi：10.1006/gcen.1994.1143
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journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.06.009
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
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doi：10.1016/j.ygcen.2013.10.012
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
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journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.07.001
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abstract：:This set of experiments investigated the role of protein kinase-C (PKC) as a second messenger in vasoactive intestinal peptide (VIP)-stimulated prolactin (PRL) secretion and PRL mRNA abundance. Dispersed anterior pituitary cells (5 x 10(5) or 10(6) cells/tube) were isolated from laying turkeys and incubated in 1.0 ml ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1112
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abstract：:Effects of epidermal growth factor (EGF) and possible mechanisms of EGF-mediated signal transduction were investigated in isolated cells of the digestive gland of the mussel (Mytilus galloprovincialis Lam. ). EGF induced a cytosolic Ca2+ transient and subsequently stimulated DNA synthesis; both effects were dose-depen...
journal_title：General and comparative endocrinology
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abstract：:The neuropeptide gonadotropin-releasing hormone (GnRH) plays an important role in the control of reproductive functions. Vertebrates possess multiple GnRH isoforms that are classified into three main groups, namely GnRH1, GnRH2 and GnRH3. In the present study, we show that the chromosomal organization of the three GnR...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2010.11.017
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.02.003
更新日期：2004-05-01 00:00:00
abstract：:Bicuspid teeth are a morphological characteristic in adult metamorphosed urodeles. However, during the mating season the males of many species of plethodontid salamanders (Urodela, Plethodontidae) from northern America bear large monocuspid teeth on their jaws. Since androgen levels are elevated during the mating seas...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00216-8
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abstract：:Three gonadotropin-releasing hormones (GnRHs) and three cognate receptors have been identified in vertebrates, with distinct distributions and functions. According to their sequences, the receptors can be grouped into distinct classes: types I, II, and III. One branch contains all type-I GnRH receptors (GnRH-R-I) from...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2005.01.019
更新日期：2005-05-15 00:00:00
abstract：:The androgen concentration in birds' eggs varies with laying order, breeding conditions, and mate attractiveness. In passerine birds, mate attractiveness depends upon song quality. The aim of our study was to evaluate the effect of one criterion used by females to assess male song quality that is to say the presence o...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.05.010
更新日期：2004-09-01 00:00:00
