Changes in cold hardiness, carbohydrate content and β-amylase gene expression were monitored in the shoots of the highbush blueberry (Vaccinium corymbosum L.) cultivars ‘Sharpblue’ and ‘Jersey’ during cold acclimation (CA) and deacclimation (DA). The seasonal patterns were similar in both cultivars, but the levels of cold hardiness determined by electrolyte leakage analysis were significantly different; ‘Jersey’ was hardier than ‘Sharpblue’. Cold hardiness was closely related to total soluble sugar content (r = −0.98** and −0.99** for ‘Sharpblue’ and ‘Jersey’, respectively). In ‘Jersey’, more soluble sugars accumulated during CA. Of the detected soluble sugars, glucose, fructose and raffinose contents were significantly associated with cold hardiness in both cultivars. Sucrose was abundant in both cultivars, and stachyose content changed significantly during CA and DA. However, they were not associated with cold hardiness. A sharp decrease in starch contents in the middle of CA coincided with β-amylase gene (VcBMY) expression, indicating the conversion of starch into soluble sugars. During CA, VcBMY was expressed up to twofold higher in ‘Jersey’ than in ‘Sharpblue’. These results suggest that intraspecies differences in the cold hardiness of highbush blueberries are associated with total soluble sugar content, which is driven partly by differential expression of VcBMY.

Highbush blueberry (Vaccinium corymbosum) fruit accumulate high levels of anthocyanins during ripening, which might be controlled by abscisic acid (ABA), a signal molecule in non-climacteric fruits. For an integrated view of the ripening process from ABA to anthocyanin biosynthesis, we analyzed the transcriptomes of ‘Bluecrop’ highbush blueberry fruit using RNA-Seq at three ripening stages, categorized based on fruit skin coloration: pale green at ca. 30 days after full bloom (DAFB), reddish purple at ca. 40 DAFB, and dark purple at ca. 50 DAFB. Mapping the trimmed reads against the reference sequences yielded 25,766 transcripts. Of these, 143 transcripts were annotated to encode five ABA biosynthesis enzymes, four ABA signal transduction regulators, four ABA-responsive transcription factors, and 12 anthocyanin biosynthesis enzymes. The analysis of differentially expressed genes between the ripening stages revealed that 11 transcripts, including those encoding nine-cis-epoxycarotenoid dioxygenase, SQUAMOSA-class MADS box transcription factor, and flavonoid 3′,5′-hydroxylase, were significantly up-regulated throughout the entire ripening stages. In fruit treated with 1 g L⁻¹ ABA, at least nine transcripts of these 11 transcripts as well as one transcript encoding flavonoid 3′-hydroxylase were up-regulated, presumably promoting anthocyanin accumulation and fruit skin coloration. These results will provide fundamental information demonstrating that ABA biosynthesis and signal transduction, and anthocyanin biosynthesis are closely associated with anthocyanin accumulation and skin coloration in highbush blueberry fruit during ripening.

Microglia play an important role in the maintenance and neuroprotection of the central nervous system (CNS) by removing pathogens, damaged neurons, and plaques. Recent observations emphasize that the promotion and development of neurodegenerative diseases (NDs) are closely related to microglial activation. In this review, we summarize the contribution of microglial activation and its associated mechanisms in NDs, such as epilepsy, Alzheimer’s disease (AD), Parkinson’s disease (PD), and Huntington’s disease (HD), based on recent observations. This review also briefly introduces experimental animal models of epilepsy, AD, PD, and HD. Thus, this review provides a better understanding of microglial functions in the development of NDs, suggesting that microglial targeting could be an effective therapeutic strategy for these diseases.

Diurnal changes of photosynthesis in the leaves of grapevine (Vitis vinifera × V. labrusca) cultivars Campbell Early and Kyoho grown in the field were compared with respect to gas exchanges and actual quantum yield of photosystem 2 (Φ_PS2) in late May. Net photosynthetic rate (P_N) of the two cultivars rapidly increased in the morning, saturated at photosynthetic photon flux density (PPFD) from 1200 to 1500 µmol m⁻² s⁻¹ between 10:00 and 12:00 and slowly decreased after midday. Maximum P_N was 13.7 and 12.5 µmol m⁻² s⁻¹ in Campbell Early and Kyoho, respectively. The stomatal conductance (g_s) and transpiration rate changed in parallel with P_N, indicating that P_N was greatly affected by g_s. However, the decrease in P_N after midday under saturating PPFD was also associated with the observed depression of Φ_PS2 at high PPFD. The substantial increase in the leaf to air vapour pressure deficit after midday might also contribute to decline of g_s and P_N.