Age-dependent degradation of amyloid precursor protein in the post-mortem mouse brain cortex

We have examined the degradation of amyloid precursor protein (APP) in the brain cortex of adult (24±2) and old (58±2) mice at different post-mortem time intervals (0, 1.5, 3, 6, 12 and 24 h). The brain cortex extract was prepared and processed for immunoblotting using antibodies against N-terminal 47–62 amino acids (Asp29) and central 301–316 amino acids containing Kunitz protease inhibitor (KPI) domain (Asp45) of APP. Asp29 (N-terminal) recognizes two bands of 140 and 112 kDa. The amount of 140 kDa is relatively higher in adult than old. The level of 112 kDa is 1.6 times lower in adult than old. It shows no remarkable change with varying post-mortem time. On the other hand, Asp45 (KPI) detects two bands of 110 and 116 kDa. While 116 kDa disappears rapidly after death of the animal, 110 kDa shows no remarkable change with different post-mortem periods. Further incubation of the disrupted tissue at 4 °C for 24 h and immunoblot analysis with Asp29 (N-terminal) shows 112 kDa in both ages but 58.5 kDa in adult and 70 kDa in old only. Analysis with Asp45 (KPI) shows only 54 kDa which increases after 3 h in adult but decreases significantly after 1.5 h and becomes undetectable at 24 h in old. Thus the present findings indicate that APP is degraded in a precise pattern and it depends on cellular intactness, post-mortem period and age of the animal.     

MAGICdb – Mango Genetic stocks Identification and Characterisation database

MAGICdb is a unique database that integrates the morphological, fruit quality and the marker data of most popular and widely cultivated commercially important mango cultivars. The main objective of MAGICdb is to provide the end users with an integrated dataset of each mango variety cultivated widely in Tamil Nadu. MAGICdb structure is categorized in to three domains namely Morphological Data Search, Fruit Quality Search and Marker Search which in further contains details on Tree Character, Bearing Habit, Season of fruiting, Number of inflorescence/Sq.m, Percentage of hermaphrodite flower(%), Fruit set percentage(%), Number of fruits/ tree, Fruit weight (g) and, Yield (Kg/ tree). This database is equipped with a user friendly interface enabling the users to retrieve the information with ease. Database is available at http://www.tnaugenomics.com/mango/index.php