Breeding has been used successfully for many years in the fruit industry, giving rise to most of today’s commercial fruit cultivars. More recently, new molecular breeding techniques have addressed some of the constraints of conventional breeding. However, the development and commercial introduction of such novel fruits has been slow and limited with only five genetically engineered fruits currently produced as commercial varieties—virus-resistant papaya and squash were commercialized 25 years ago, whereas insect-resistant eggplant, non-browning apple, and pink-fleshed pineapple have been approved for commercialization within the last 6 years and production continues to increase every year. Advances in molecular genetics, particularly the new wave of genome editing technologies, provide opportunities to develop new fruit cultivars more rapidly. Our review, emphasizes the socioeconomic impact of current commercial fruit cultivars developed by genetic engineering and the potential impact of genome editing on the development of improved cultivars at an accelerated rate.
Summary: Infectious diseases, also known as transmissible or communicable diseases, are caused by pathogens or parasites that spread in communities by direct contact with infected individuals or contaminated materials, through droplets and aerosols, or via vectors such as insects. Such diseases cause ˜17% of all human deaths and their management and control places an immense burden on healthcare systems worldwide. Traditional approaches for the prevention and control of infectious diseases include vaccination programmes, hygiene measures and drugs that suppress the pathogen, treat the disease symptoms or attenuate aggressive reactions of the host immune system. The provision of vaccines and biologic drugs such as antibodies is hampered by the high cost and limited scalability of traditional manufacturing platforms based on microbial and animal cells, particularly in developing countries where infectious diseases are prevalent and poorly controlled. Molecular farming, which uses plants for protein expression, is a promising strategy to address the drawbacks of current manufacturing platforms. In this review article, we consider the potential of molecular farming to address healthcare demands for the most prevalent and important epidemic and pandemic diseases, focussing on recent outbreaks of high‐mortality coronavirus infections and diseases that disproportionately affect the developing world.
SUMMARY: Saffron spice owes its commercial appreciation to its specific apocarotenoids: crocins, picrocrocin, and safranal. In Crocus sativus, these compounds are biosynthesized from zeaxanthin through oxidative cleavage by the carotenoid cleavage dioxygenase 2 (CCD2). Transgenic tomato plants expressing CsCCD2 in the fruit, named Tomaffron, accumulate high levels of saffron apocarotenoids despite the low substrate availability for CsCCD2. In the present study, CsCCD2 has been introduced into Xantomato; this tomato variety accumulates high levels of zeaxanthin and β‐carotene in ripe fruit due to a combination of four mutant alleles. Xantomato and Tomaffron genotypes have been combined to optimize apocarotenoid production. The best transgenic lines accumulated 15 and 14 times more crocins and picrocrocin than Tomaffron, alongside a fourfold increase in β‐carotene compared to Xantomato, albeit at a cost in fruit yield. Segregation of the four mutations has been carried out to find the best combination for obtaining high levels of saffron apocarotenoids without adverse effects on fruit yield. Plants harboring the high‐pigmented 3 (hp3) and BETA (BSh) mutations accumulated 6 and 15 times more crocins and picrocrocin than Tomaffron, without observable pleiotropic effects. Additionally, those high levels of saffron apocarotenoids were obtained in fruit accumulating high levels of both lycopene and β‐carotene independently or in combination, suggesting a regulatory role for the apocarotenoids produced and indicating that it is possible to increase the levels of both types of healthy promoting molecules simultaneously.
A dose of proanthocyanidins with satiating properties proved to be able to limit body weight increase several weeks after administration under exposure to a cafeteria diet. Here we describe some of the molecular targets and the duration of the effects. We treated rats with 500 mg grape seed proanthocyanidin extract (GSPE)/kg BW for ten days. Seven or seventeen weeks after the last GSPE dose, while animals were on a cafeteria diet, we used reverse transcriptase-polymerase chain reaction (RT-PCR) to measure the mRNA of the key energy metabolism enzymes from the liver, adipose depots and muscle. We found that a reduction in the expression of adipose Lpl might explain the lower amount of adipose tissue in rats seven weeks after the last GSPE dose. The liver showed increased expression of Cpt1a and Hmgs2 together with a reduction in Fasn and Dgat2. In addition, muscle showed a higher fatty oxidation (Oxct1 and Cpt1b mRNA). However, after seventeen weeks, there was a completely different gene expression pattern. At the conclusion of the study, seven weeks after the last GSPE administration there was a limitation in adipose accrual that might be mediated by an inhibition of the gene expression of the adipose tissue Lpl. Concomitantly there was an increase in fatty acid oxidation in liver and muscle.
Efficient isolation of male gametes has enabled unprecedented advances in omics research, crucial for elucidating the molecular mechanisms governing male gametogenesis and fertilization. In this study, we developed a method for isolating generative and sperm cells from the economically important crop Solanum lycopersicum (tomato). A double fluorescent marker line was generated in the tomato variety Micro-Tom, employing mTurquoise and mScarlet-I fluorescent proteins under the control of promoters exhibiting preferential activity in generative and sperm cells, respectively. Then we developed a protocol that combines male gamete release from pollen grains and pollen tubes of this double fluorescent marker line and SYTOX Red live/dead cell stain to obtain viable cells by fluorescence-activated cell sorting. This allows the isolation of generative cells from mature pollen grains, and of sperm cells from pollen tubes after semi-in vivo growth, in both high quantity and purity. Additionally, an unexpected mScarlet-I signal in the vegetative nucleus, that persists until the sperm cells are formed, allows the sorting of vegetative nuclei. We anticipate that our novel double marker line will accelerate research into tomato male gametogenesis, thereby enhancing efforts to improve the resilience of fertilization processes to climate change.