Treatment of donor cells with trichostatin A improves in vitro development and reprogramming of buffalo (Bubalus bubalis) nucleus transfer embryos

It has been reported that buffalo (Bubalus bubalis) embryos reconstructed by somatic cell nucleus transfer (SCNT) can develop to the full term of gestation and result in newborn calves. However, the developmental competence of reconstructed embryos is still low. Recently, it has been reported that treating donor cells or embryos with trichostatin A (TSA) can increase the cloning efficiency in some species. Thus, the present study was undertaken to improve the development of buffalo SCNT embryos by treatment of donor cells (buffalo fetal fibroblasts) with TSA and explore the relation between histone acetylation status of donor cells and developmental competence of SCNT embryos. Treatment of donor cells with either 0.15 or 0.3 μM TSA for 48 hours resulted in a significant increase in the cleavage rate and blastocyst yield of SCNT embryos (P < 0.05). Meanwhile, the expression level of HDAC1 in donor cells was also decreased (0.4–0.6 fold, P < 0.05) by TSA treatment, although the expression level of HAT1 was not affected. Further measurement of the epigenetic maker AcH4K8 in buffalo IVF and SCNT embryos at the eight-cell stage revealed that the spatial distribution of acH4K8 staining in SCNT embryos was different from the IVF embryos. Treatment of donor cells with TSA resulted in an increase in the AcH4K8 level of SCNT embryos and similar to fertilized counterparts. These results suggest that treatment of donor cells with TSA can facilitate their nucleus reprogramming by affecting the acetylated status of H4K8 and improving the in vitro development of buffalo SCNT embryos. The AcH4K8 status at the eight-cell stage can be used as an epigenetic marker for predicting the SCNT efficiency in buffalos.     

Five new nomenclatural combinations in Dasymaschalon and Goniothalamus (Annonaceae)

Three new nomenclatural combinations are validated in Dasymaschalon (Annonaceae), with the elevation of varietal names to the specific rank: D. longiusculum (Bân) Jing Wang & R. M. K. Saunders, D. megalanthum (Merr.) Jing Wang & R. M. K. Saunders, and D. minutiflorum (Nurmawati) Jing Wang & R. M. K. Saunders. New nomenclatural combinations are furthermore validated in Goniothalamus (Annonaceae), following the successful conservation of the generic name over Richella. Two species names in Richella are here transferred to Goniothalamus as G. monospermus (A. Gray) R. M. K. Saunders and G. obtusatus (Baill.) R. M. K. Saunders.     

An efficient protocol for stimulating cell development in protoplast culture of S<Emphasis Type=Italic>caevola</Emphasis>

Scaevola, characterised by unique fan-shaped flowers, is an Australian endemic ornamental having a great commercial potential. The breeding of Scaevola however is limited due to poor seed germination, therefore it is critical to understand the embryogenesis in Scaevola so as to facilitate its breeding improvement programs. Direct differentiation of embryo structures was first reported here in mesophyll protoplast cultures of Scaevola aemula. The isolated protoplasts initiated cell division when cultured in KM or MS medium. Higher plating efficiencies were observed in the medium containing a combination of NAA and BAP in contrast to 2,4-D and BAP. The formation of globular embryo structures was successfully achieved. This protoplast culture system can be utilized as an experimental platform for the study of embryogenic differentiation of cells. It may open new vistas to investigate the seed development at molecular and cellular levels in Scaevola and related Australian native plants that are well known for their low seed viability and germination.     

SD-RLK28 positively regulates pollen hydration on stigmas as a PCP-Bβ receptor in Arabidopsis thaliana

Pollen hydration on dry stigmas is strictly regulated by pollen–stigma interactions in Brassicaceae. Although several related molecular events have been described, the molecular mechanism underlying pollen hydration remains elusive. Multiple B-class pollen coat proteins(PCP-Bs) are involved in pollen hydration. Here, by analyzing the interactions of two PCP-Bs with three Arabidopsis thaliana stigmas strongly expressing S-domain receptor kinase(SD-RLK), we determined that SD-RLK28 directly intera...