Establishment of testis-specific SOX9 activation requires high-glucose metabolism in mouse sex differentiation

AbstractIn mouse sex differentiation, SRY promotes Sertoli cell differentiation via SOX9 action, resulting in testis formation. SRY/SOX9 also initiates various testis-specific morphogenic events including glycogenesis in pre-Sertoli cells, suggesting the importance of glucose storage for certain SRY/SOX9-downstream events in gonadal sex determination. However, it remains unclear which cell types and what molecular/cellular events require sex-dimorphic high-energy metabolic rate. Here we show that the establishment of SOX9 activation itself is a metabolically active process with sex-dimorphic high-energy requirements in gonadal sex differentiation. The glucose-deprivation and metabolic rescue experiments using genital ridge cultures of the XY/XX-wildtype and XX/Sry transgenic embryos demonstrated that, among the various somatic cell types, pre-Sertoli cells are the most sensitive to glucose starvation despite the differences between XX/Sry and XY genotypes. Moreover, our data showed that, in developing pre-Sertoli cells, the high-glucose metabolic state is required for the establishment of SOX9 expression through an ECM (extracellular matrix)-mediated feed-forward pathway. In contrast, the expression of SRY, SF1/Ad4Bp, GATA4 and WT1, as well as initiation of early SOX9 expression, is properly maintained in the glucose-deprived condition. Therefore, our results imply the metabolic importance of the high-glucose condition for the establishment of SOX9 activation in testis differentiation

Mikroskopska istraživanja stijenki glavnih arterija za opskrbljivanje mliječnih žlijezda zamorčeta (Cavia porcellus) u različitim reprodukcijskim stadijima.

A microscopic studies on the arterial wall of main arteries supplying the mammary glands of guinea pig at different reproductive stages was carried out by using a light microscope. The arterial segments from the ascending aorta to the mammary glands were classified into elastic, transitional and muscular types. The ascending aorta, aortic arch, brachiocephalic trunk, the subclavian, the thoracic, and abdominal aorta were elastic type. The subendothelial layer was present. The tunica media contained of well- defined elastic lamellae. The maximum numbers of elastic lamellae were recorded as 25-30, in the ascending aorta. The common iliac, the proximal and distal parts of the external iliac, and the proximal part of the femoral arteries were transitional type. The transitional type had the characteristics feature of both elastic and muscular types. The deep femoral, pudendoepigastric trunk, the external pudendal, the caudal superficial epigastric, and the caudal and cranial mammary arteries were muscular type. The tunica media was completely devoid of elastic lamellae. The reproductive stages did not affect the general histology of the large and medium size arteries. But the internal elastic membrane of the external pudendal, caudal superficial epigastric, and mammary arteries were wavy in the virgin stage. This wavy character was lost following pregnancy to the on the onset of lactation. It may beassumed that, during lactating period increased volume and force flow of blood through these arteries gives pressure to the inner arterial wall resulting straightening of the internal elastic membrane. The existence of elastic lamellae in the elastic arteries, probably due to resist comparatively high arterial pressure compared to that of the peripheral muscular arteries.Obavljeno je mikroskopsko istraživanje stijenki glavnih arterija koje opskrbljuju krvlju mliječnu žlijezdu zamorčeta tijekom različitih faza reprodukcije. Arterijski segmenti uzlaznog dijela aorte klasificirani su kao elastični, prijelazni i mišićni tip. Uzlazni dio aorte, brahiocefalični trunkus, supklavijalna, torakalna i abdominalna aorta elastičnog su tipa s prisutnim subendotelijalnim slojem. Tunika medija sadrži dobro definirane elastične lamele kojih u uzlazne aorte ima 25 do 30. Zajednička ilijačna, proksimalni i distalni dio vanjske ilijačne arterije i proksimalni dio femoralnih arterija prijelaznog su tipa koji ima karakteristike elastičnoga i mišićnoga epitela. Dubinska femoralna arterija, pudendoepigastrični trunkus, vanjska pudendalna arterija, kaudalna superficijalna epigastrična arterija te kaudalne i kranijalne mamarne arterije mišićnoga su tipa. Tunika medija u navedenih arterija upotpunosti je bez elastičnih lamela. Potrebno je istaknuti da različite faze reprodukcije ne utječu na histološku građu velikih i malih arterija. U razdoblju prije gravidnosti zapažena je valovitost interne elastične membrane vanjske pudendalne arterije, kaudalne superficijalne epigastrične te mamarne arterije koja se gubi nakon nastupa gravidnosti pa sve do razdoblja laktacije. Pretpostavlja se da je to odgovor na povećan protok krvi koji svojim tlakom mijenja ujedno i morfologiju interne elastične membrane

Invazija miksosporidijama na škrgama i koži šarana u uzgajalištima u Bangladešu: patohistološki nalaz.

Histopathological studies of gills and skin of juvenile carp infected with myxosporidian protozoans in two fish farms (Trisal Government fish farm and Jhalak Private fish farm) of Mymensingh district in Bangladesh were carried out during the period September to December 1994. A total of 140 carp ranging from 4 to12 cm in total length were examined and comprised 70 Labeo rohita (L. rohita), and 70 Cirrhina mrigala (C. mrigala). Samplings were carried out at 15 -day intervals. Pathological symptoms were more prominent in carp at the Government fish farm (GFF) than in those at the Private fish farm (PFF). Marked pathological changes were limited to the gills and skin of C. mrigala at the GFF in December 1994. Hyperplasia and hypertrophy, with presence of numerous inflammatory cells and an accumulation of blood cells, were observed at the base of secondary gill lamellae of C. mrigala at the GFF. Myxosporidian cysts, identified as Myxobolus spp. and full of mature spores, were attached to the secondary gill lamellae. A significantly increased number of cysts were recognizedin the gills of C. mrigala at the GFF compared to those of L. rohita at the PFF. The skin of C. mrigala at the GFF exhibited an increased number of pathological changes. Epidermis and dermis sloughed off, the dermal layer split into a few parts, and Myxosporidian cysts full of mature spores appeared in the skin of C. mrigala. At the PFF, the skin of L. rohita was less infected than C. mrigala. Apparently healthy fish fry was found to be free from cysts. No significant differences of water quality parameters were recorded at either fish farm. Carp at the PFF were less infected than those at the GFF, probably due to its better management practices.Patohistološka istraživanja škrga i kože mladih šarana invadiranih mikrosporidijima uzgajanih u dva ribnjaka na području Mymensingha u Bangladešu provedena su u razdoblju od rujna 1994. do prosinca 1994. Ukupno je bilo pretraženo 140 šarana (70 vrste Labeo rohita i 70 vrste Cirrhina mrigala) veličine od 4 do 12 cm. Uzorci su uzeti svakih 15 dana. Patološki su znakovi bili učestaliji u šarana podrijetlom iz državnih ribnjaka u odnosu na one iz privatnih ribnjaka. Najveće su promjene utvrđene u vrste C. mrigala. Hiperplazija i hipertrofija te veliki broj upalnih stanica utvrđen je na bazi sekundarne škržne lamele u iste vrste šarana. Ciste s potpuno zrelim sporama identificirane su kao Myxobolus sp. Iste su ciste češće pronađene na škrgama šarana podrijetlom iz državnih ribnjaka. U šarana podrijetlom iz državnih farmi učestalije su utvrđene promjene i na koži, i to u epidermisu i dermisu. Ciste nisu utvrđene u mlađi. Tijekom istraživanja nisu utvrđene nikakve razlike u kakvoći vode. Na osnovi nalaza može se smatrati da je manja invadiranost šarana podrijetlom iz privatnih ribnjaka uvjetovana boljom tehnologijom

Distribution of lectin-bindings in the testis of the lesser mouse deer, Tragulus javanicus

The distribution of lectin bindings in the testis of the smallest ruminant, lesser mouse deer (Tragulus javanicus), was studied using 12 biotinylated lectins specific for d-galactose (peanut agglutinin PNA, Ricinus communis agglutinin RCA I), N-acetyl-d-galactosamine (Dolichos biflorus agglutinin DBA, Vicia villosa agglutinin VVA, Soybean agglutinin SBA), N-acetyl-d-glucosamine and sialic acid (wheat germ agglutinin WGA, s-WGA), d-mannose and d-glucose (Lens culinaris agglutinin LCA, Pisum sativum agglutinin PSA, Concanavalin A Con A), l-fucose (Ulex europaeus agglutinin UEA I), and oligosaccharide (Phaseolus vulgaris agglutinin PHA-E) sugar residues. In Golgi-, cap-, and acrosome-phase spermatids, lectin-bindings were found in the acrosome (PNA, RCA I, VVA, SBA, WGA and s-WGA), and in the cytoplasm (PNA, RCA I, VVA, SBA, WGA, LCA, PSA, Con A and PHA-E). s-WGA binding was confined to the spermatid acrosome, but other lectins were also observed in spermatocytes. In spermatogonia, VVA, WGA, Con A, and PHA-E bindings were observed. Sertoli cells were intensely stained with DBA and Con A, and weakly with PHA-E. In interstitial Leydig cells, RCA I, DBA, VVA, Con A, PSA, LCA, WGA and PHA-E were positive. UEA I was negative in all cell types including spermatogenic cells. Unusual distribution of lectin-bindings noted in the testis of lesser mouse deer included the limited distribution of s-WGA only in the spermatid acrosome, the distribution of DBA in Sertoli cells, Leydig cells and lamina propria, and the absence of UEA I in all type cells. The present results were discussed in comparison with those of other animals and their possible functional implications

A critical time window of Sry action in gonadal sex determination in mice

In mammals, the Y-linked sex-determining gene Sry cell-autonomously promotes Sertoli cell differentiation from bipotential supporting cell precursors through SRY-box containing gene 9 (Sox9), leading to testis formation. Without Sry action, the supporting cells differentiate into granulosa cells, resulting in ovarian development. However, how Sry acts spatiotemporally to switch supporting cells from the female to the male pathway is poorly understood. We created a novel transgenic mouse line bearing an inducible Sry transgene under the control of the Hsp70.3 promoter. Analysis of these mice demonstrated that the ability of Sry to induce testis development is limited to approximately 11.0-11.25 dpc, corresponding to a time window of only 6 hours after the normal onset of Sry expression in XY gonads. If Sry was activated after 11.3 dpc, Sox9 activation was not maintained, resulting in ovarian development. This time window is delimited by the ability to engage the high-FGF9/low-WNT4 signaling states required for Sertoli cell establishment and cord organization. Our results indicate the overarching importance of Sry action in the initial 6-hour phase for the female-to-male switching of FGF9/WNT4 signaling patterns

Cyclical and Patch-Like GDNF Distribution along the Basal Surface of Sertoli Cells in Mouse and Hamster Testes

BACKGROUND AND AIMS: In mammalian spermatogenesis, glial cell line-derived neurotrophic factor (GDNF) is one of the major Sertoli cell-derived factors which regulates the maintenance of undifferentiated spermatogonia including spermatogonial stem cells (SSCs) through GDNF family receptor α1 (GFRα1). It remains unclear as to when, where and how GDNF molecules are produced and exposed to the GFRα1-positive spermatogonia in vivo. METHODOLOGY AND PRINCIPAL FINDINGS: Here we show the cyclical and patch-like distribution of immunoreactive GDNF-positive signals and their close co-localization with a subpopulation of GFRα1-positive spermatogonia along the basal surface of Sertoli cells in mice and hamsters. Anti-GDNF section immunostaining revealed that GDNF-positive signals are mainly cytoplasmic and observed specifically in the Sertoli cells in a species-specific as well as a seminiferous cycle- and spermatogenic activity-dependent manner. In contrast to the ubiquitous GDNF signals in mouse testes, high levels of its signals were cyclically observed in hamster testes prior to spermiation. Whole-mount anti-GDNF staining of the seminiferous tubules successfully visualized the cyclical and patch-like extracellular distribution of GDNF-positive granular deposits along the basal surface of Sertoli cells in both species. Double-staining of GDNF and GFRα1 demonstrated the close co-localization of GDNF deposits and a subpopulation of GFRα1-positive spermatogonia. In both species, GFRα1-positive cells showed a slender bipolar shape as well as a tendency for increased cell numbers in the GDNF-enriched area, as compared with those in the GDNF-low/negative area of the seminiferous tubules. CONCLUSION/SIGNIFICANCE: Our data provide direct evidence of regionally defined patch-like GDNF-positive signal site in which GFRα1-positive spermatogonia possibly interact with GDNF in the basal compartment of the seminiferous tubules

CT examination of the manipulation system in the giant panda (Ailuropoda melanoleuca)

The manipulation mechanism of the giant panda (Ailuropida melanoleuca) was examined by means of CT (computed tomography) and 3-dimensional (3-D) Volume Rendering techniques. In the 3-D images of the giant panda hand, not only the bones but also the muscular system was visualised. Sections of the articulated skeleton were obtained. It was demonstrated that the hand of the panda is equipped with separately moulded manipulation units as follows: (1) the radial sesamoid (RS), the radial carpal, and the first metacarpal (R–R–M) complex; and (2) the accessory carpal (AC) and the ulnar (A–U) complex. When the giant panda grasps anything, the R–R–M complex strongly flexes at the wrist joint, the RS becomes parallel with the AC, and the phalanges bend and hold the object. It is shown that the well-developed opponens pollicis and abductor pollicis brevis muscles envelop and fix the objects between the R–R–M complex and the phalanges during grasping