SUMMARY: An efficient procedure has been developed and subsequently simplified for in vitro maturation and in vitro fertilization (IVF) of bovine follicular oocytes obtained from abattoir ovaries. After in vitro fertilization, successful cleavage and in vitro development were obtained using a simple and efficient cumulus cell co-culture method, which consistently produced 45 to 50% morulae during the treatment and culture of over 6000 bovine oocytes. Embryonic cell number for IVF-derived embryos was monitored at different stages of in vitro development during cumulus cell co-culture to evaluate embryo growth and assess embryo quality.
Maize (Zea mays L.) is one of the major crops susceptible to Aspergillus flavus Link ex. Fries infection and subsequent aflatoxin contamination. Previous studies found the production of an antifungal 14 kDa trypsin inhibitor (TI) was associated with maize aflatoxin resistance. To further investigate whether the TI plays any direct role in resistance, a TI gene silencing vector was constructed and transformed into maize. Mature kernels were produced from 66 transgenic lines representing 18 independent events. A final total of twelve lines representing four independent events were confirmed positive for transformation, five of which showed significant reduction (63 to 88%) in TI transcript abundance in seedling leaf tissue and seven of which showed significant TI protein reduction (39-85%) in mature kernels. Six of the seven silenced transgenic lines supported higher levels of aflatoxin production compared to negative controls. To further confirm the role of TI in field resistance to aflatoxin accumulation, DNA sequence polymorphisms from within the gene or linked simple sequence repeats were tested in four quantitative trait loci (QTL) mapping populations for QTL effect, and three QTL with log of the odds scores of 11, 4.5, and 3.0 and possibly caused by the TI protein encoding gene were found. Sequence polymorphisms were also tested for association to aflatoxin levels in an association mapping panel, and three single nucleotide polymorphisms were found associated with aflatoxin accumulation (P<0.01). The data from both RNAi and genetic mapping studies demonstrated that production of the TI in maize is important for its resistance to A. flavus infection and/or aflatoxin production.
kSll01Wl1 (J)NJNt AitNi iONS ,\ltCi latixclx' the impliepmielnt'tatioi of t ansahbdominal Util SOnl()g0rlalphic examination in many hlorscs hlas improxed the diagnosis of di tf-ci cut discascs. In the pi cscnIt case, the
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.