SEPALLATA1/2-suppressed mature apples have low ethylene, high auxin and reduced transcription of ripening-related genes

BACKGROUND AND AIMS

Fruit ripening is an important developmental trait in fleshy fruits, making the fruit palatable for seed dispersers. In some fruit species, there is a strong association between auxin concentrations and fruit ripening. We investigated the relationship between auxin concentrations and the onset of ethylene-related ripening in Malus × domestica (apples) at both the hormone and transcriptome levels.

METHODOLOGY

Transgenic apples suppressed for the SEPALLATA1/2 (SEP1/2) class of gene (MADS8/9) that showed severely reduced ripening were compared with untransformed control apples. In each apple type, free indole-3-acetic acid (IAA) concentrations were measured during early ripening. The changes observed in auxin were assessed in light of global changes in gene expression.

PRINCIPAL RESULTS

It was found that mature MADS8/9-suppressed apples had a higher concentration of free IAA. This was associated with increased expression of the auxin biosynthetic genes in the indole-3-acetamide pathway. Additionally, in the MADS8/9-suppressed apples, there was less expression of the GH3 auxin-conjugating enzymes. A number of genes involved in the auxin-regulated transcription (AUX/IAA and ARF classes of genes) were also observed to change in expression, suggesting a mechanism for signal transduction at the start of ripening.

CONCLUSIONS

The delay in ripening observed in MADS8/9-suppressed apples may be partly due to high auxin concentrations. We propose that, to achieve low auxin associated with fruit maturation, the auxin homeostasis is controlled in a two-pronged manner: (i) by the reduction in biosynthesis and (ii) by an increase in auxin conjugation. This is associated with the change in expression of auxin-signalling genes and the up-regulation of ripening-related genes.

Role of blood bag temperature indicators in maintaining patent temperature of the returned unused blood bags in blood bank

BACKGROUND AND AIMS

The main objective of the present study was to evaluate the temperature chain of red blood cells (RBC) returned unused blood bags using blood temperature indicator and ascertain the factors like transportation time, type, size of coolant box and number of bags per box.

MATERIALS AND METHODS

A total of 250 blood bags with the indicator were observed for the temperature changes with other factors like transportation time, type and size of coolant box and number of bags per box. The recordings were performed at several checkpoints located between the blood bank and the wards.

RESULTS

Out of the 250 bags, 74 (29.6%) showed colour changes in which 64 (86.3%) were returned unused (RU) blood bags. The transportation time for these 74 bags was 818.3 ± 941.643 min, significantly higher than bags without colour changes, (p=0.02). Interestingly, 71.4% of the colour changes occurred within the ward. The 7 litre coolant box with an average of 1-5 blood bags per box had a statistically significant higher percentage of colour change with 59.2% compared to the 5 litre coolant box (p=0.05).

CONCLUSION

This study showed that the temperature chain of blood bags was often not well maintained. These results could be mainly due to the non-adherence to the standard operating procedure (SOP) of blood transfusion and the usage of non-standardized coolant boxes.