Spatial and temporal expression of germ cell nuclear factorin murine epididymis

Aim: To investigate the spatial and temporal expression of germ cell nuclear factor (GCNF) in mouse and rat epididymis during postnatal period. Methods: The epididymal sections from different postnatal days were stained for GCNF by the indirect immunofluorescence technique and digital photographs were taken by a Carl Zeiss confocal microscope. Results: GCNF was first detected on day 12 in mouse epididymis and day 14 in rat epididymis. The highest expression of GCNF was observed on day 35 in both mouse and rat epididymis. In adults, GCNF exhibited a region-specific expression pattern, i.e., it was expressed predominantly in the initial segment, caput and proximal corpus of rat epididymis and was abundant in the proximal corpus of mouse epididymis. GCNF could be found in the nuclei of the principal, apical, narrow, clear and halo cells. Conclusion: GCNF may play an important role in epididymal differentiation and development and in sperm maturation.

Temporal expression of c-kit in spermatogenesis of two grasshopper species

Two species of grasshoppers, Calliptamus abbreviatus （Ikonn.） and Shirakiacris shirakii （I. Bol.）, were collected randomly in the Siping area of Jilin Province, China. By using immunohistochemical methods and statistical analysis, we observed and compared the temporal expression of c-kit protein in four representative stages of spermatogenesis of the two grasshoppers, namely： spermatogonia; primary spermatocyte; secondary spermatocyte; and mature sperm. Results showed that there was c-kit positive temporal expression at each stage of spermatogenesis, but there were different positive expression levels： （i） weak positive expression of c-kit protein appeared in spermatogonia and the positive granules were thinner; （ii） strong positive expression of c-kit protein existed in primary spermatocyte and positive granules became biggest among all developmental stages; （iii） c-kit positive expression stayed stronger in secondary spermatocyte while positive granules became thinner; （iv） there was a strong positive expression of c-kit and thinner positive granules in mature sperm, which distributed on head and tail; （v） the biggest c-kit positive granules had been found massing at the end of spermary; and （vi） significant differences of c-kit positive expression existed in spermatogenesis between two species of grasshoppers. The results indicated that c-kit protein may play a crucial role in spermatogenesis and even retain the physiological action of sperms and fertilization in grasshoppers.

Expression of germ cell nuclear factor in mouse germ cells and sperm during postnatal period

Aim: To assess the spatial and temporal expression of germ cell nuclear factor (GCNF) in male mouse germ cells during postnatal development and in sperm before and after capacitation. Methods: The indirect immun-ofluorescence method with anti-GCNF antiserum was used to investigate the GCNF expression in mice at day 8, 10, 14, 17, 20, 28, 35, 70, and 420 after birth and in sperm before and after capacitation. Results: With the proceeding of spermatogenesis, GCNF was first detected in the nuclei of spermatogonia and a few early stage primary sperma-tocytes at day 8, which was increased gradually at day 10 to 14 inclusive. From day 17 to day 20, the GCNF was concentrated in round spermatids, while both spermatogonia and early stage primary spermatocytes became GCNF negative. From day 28 until day 420, strong GCNF expression was shown in round spermatids and pachytene spermatocytes, while spermatogonia, early primary spermatocytes and elongating spermatids were all GCNF negative. In addition, it was also found that GCNF was localized on the acrosomal cap region of spermatozoa and there was a big change in GCNF expression during capacitation, from 98 % GCNF positive before capacitation to about 20 % positive following capacitation. The localization of GCNF in caput and cauda spermatozoa was similar. Conclusion: GCNF may play important roles in spermatogenesis, capacitation and fertilization.

Temporal control of the Aux/IAA genes BnIAA32 and BnIAA34 mediates Brassica napus dual shade responses

Precise responses to changes in light quality are crucial for plant growth and development.For example,hypocotyls of shade-avoiding plants typically elongate under shade conditions.Although this typical shade-avoidance response(TSR)has been studied in Arabidopsis(Arabidopsis thaliana),the molecular mechanisms underlying shade tolerance are poorly understood.Here we report that B.napus(Brassica napus)seedlings exhibit dual shade responses.In addition to the TSR,B.napus seedlings also display an atypical shade response(ASR),with shorter hypocotyls upon perception of early-shade cues.Genome-wide selective sweep analysis indicated that ASR is associated with light and auxin signaling.Moreover,genetic studies demonstrated that phytochrome A(BnphyA)promotes ASR,whereas BnphyB inhibits it.During ASR,YUCCA8 expression is activated by early-shade cues,leading to increased auxin biosynthesis.This inhibits hypocotyl elongation,as young B.napus seedlings are highly sensitive to auxin.Notably,two non-canonical AUXIN/INDOLE-3-ACETIC ACID(Aux/IAA)repressor genes,BnIAA32 and BnIAA34,are expressed during this early stage.BnIAA32 and BnIAA34 inhibit hypocotyl elongation under shade conditions,and mutations in BnIAA32 and BnIAA34 suppress ASR.Collectively,our study demonstrates that the temporal expression of BnIAA32 and BnIAA34 determines the behavior of B.napus seedlings following shade-induced auxin biosynthesis.

Tissue-specific Temporal Exome Capture Revealed Muscle-specific Genes and SNPs in Indian Buffalo(Bubalus bubalis)

Whole genome sequencing of buffalo is yet to be completed, and in the near future it may not be possible to identify an exome （coding region of genome） through bioinformatics for designing probes to capture it. In the present study, we employed in solution hybridization to sequence tissue specific temporal exomes （TST exome） in buffalo. We utilized cDNA prepared from buffalo muscle tissue as a probe to capture TST exomes from the buffalo genome. This resulted in a prominent reduction of repeat sequences （up to 40%） and an enrichment of coding sequences （up to 60%）. Enriched targets were sequenced on a 454 pyro-sequencing platform, generating 101,244 reads contain- ing 24,127,779 high quality bases. The data revealed 40,100 variations, of which 403 were indels and 39,218 SNPs containing 195 nonsyn- onymous candidate SNPs in protein-coding regions. The study has indicated that 80% of the total genes identified from capture data were expressed in muscle tissue. The present study is the first of its kind to sequence TST exomes captured by use of cDNA molecules for SNPs found in the coding region without any prior sequence information of targeted molecules.