An Evidence of Enhanced Fitness by Male Remounting during the Courtship in three Species of Montium Subgroup of Drosophila
Sowmya M. L.,
S. N. Hegde
Issue:
Volume 2, Issue 3, June 2014
Pages:
37-43
Received:
20 May 2014
Accepted:
7 July 2014
Published:
30 August 2014
Abstract: Male mating a second female after first mate (male remating) is a common feature in Drosophila, particularly in mass culture. On the other hand, female remating is not as frequent as that of male remating because the sperms introduced along with the semen into the spermatheca are stored there. However, the phenomena of female remating have been reported in few species. During sexual activity, the males and females are involved an elaborate courtship at the end of which the male mounts on to the female followed by mating. During each mating, the mounted male through its ejaculate, transmits the sperms into the females' genital tract where it is stored. The sperms are stored in the spermatheca. Usually, with one mount maximum sperms are transferred to female hence second mounting does not occur. In most Drosophila, when a male mounts a female after an elaborate courtship, the pairs remain in cupola for a fixed period then dismounts. No more courtship or mounting is performed by the male towards the same female. In D.jambulina, D.nagarholensis and D.gangotrii remounting occurs two or three times immediately after the first mount. The reason for remounting has been analyzed in the present study through measuring the width of the female reproductive tract and sperm count after each mount. The female reproductive tract was dissected out and width of uterus was measured. The result showed significant difference in the width after each mount. The sperm count of these species after each mount also showed significant variation. Remounting perhaps enhances the fitness of the mating pairs.
Abstract: Male mating a second female after first mate (male remating) is a common feature in Drosophila, particularly in mass culture. On the other hand, female remating is not as frequent as that of male remating because the sperms introduced along with the semen into the spermatheca are stored there. However, the phenomena of female remating have been rep...
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MiR-145 Regulates Hematopoiesis during Zebrafish Development
Ziyad Tariq Muhseen,
Nibras Najm Abbood
Issue:
Volume 2, Issue 3, June 2014
Pages:
44-54
Received:
8 August 2014
Accepted:
27 August 2014
Published:
20 September 2014
Abstract: MicroRNA-145 (miR-145) is considered to play key role in many cellular processes, such as proliferation, differentiation and apoptosis by inhibiting target gene expression. The transcriptional regulation of cardiovascular development requires precise spatiotemporal control of gene expression. We are beginning to understand the functions of miRNA-145 played during essential biological processes especially erythropoiesis. Here, we overview the recent findings on miRNA-145 regulation in erythropoiesis development and report the latest advances in understanding their function by unveiling their mRNA targets. Further analysis of miRNA-145 function during erythropoiesis development will allow us to determine the potential for novel miRNA-145-based therapeutic strategies. Haematopoiesis is an active process by which peripheral blood families are developed. It is a process strongly regulated by many essential and unessential factors, including signalling molecules and transcriptional factors. However, the epigenetic regulation of haematopoiesis regulation via microRNAs (miRNAs) remains partially understood. Here, in this study we show that miRNA-145 participates in the haematopoiesis regulation and vascular development of the early stages of erythropoiesis during Zebra fish early developmental stages. Overexpression inhibited the primitive haematopoiesis, characterized by a significant reduced number and limitation of erythropoiesis cells and myeloid expansion significantly reduced expression of runx1, c-myb, mpo-1, Scl and pu.1, and significantly reduced o-dianisidine staining of haemoglobin. Systematically, miR-145 regulates haematopoiesis by repressing expression of meis1 involved in haematopoiesis. We performed knock-down analysis of the meis1 gene to check and demonstrate that whether meis1-EGFP is related with our miRNA. Co-injection-confirmation at 24 and 48 hpf pictures analyses showed that overexpression of miR-145 repressed expression of meis1. Bioinformatics analysis predicts a target binding sequence for miR-145 at the 3-UTR of meis1. Deletion of the miR-145 target sequence eliminated the repression of meis1 expression mediated by miR-145. These findings create miR-145 as a novel miRNA that regulates haematopoiesis and vascular development by repressing expression of meis1.
Abstract: MicroRNA-145 (miR-145) is considered to play key role in many cellular processes, such as proliferation, differentiation and apoptosis by inhibiting target gene expression. The transcriptional regulation of cardiovascular development requires precise spatiotemporal control of gene expression. We are beginning to understand the functions of miRNA-14...
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