Summary of CUBE Chatshaala Discussion (04/03/23)

We discussed on Best Poster prsentation award winning poster at ISEB 4…

While discussion, @Theertha gave nice introduction about Psyche butterflies and their host plants. Psyche butterfly is small white colour butterfly having roundish black spot on it upper wing.

According to research papers of host plants of Psyche butterfly((PDF) Comparison of oviposition and larval development of Leptosia nina Fabricius (Lepidoptera: Pieridae) on two different food plants in different seasons | Basant Agarwala -
Cleome, Capparis, Creteva plants are the host plants on which Psyche butterflies laid egg and complete its lifecycle. But there were no papers (expect paper published by CUBist) for Cardamine as host plants for Psyche butterfly

While discussing, @Abhi0703 & @Theertha added most interesting part of poster i.e. research question- What is a coevolutionary mechanism between selection of host plants by Psyche butterfly?

For understanding coevolution, we took example of Psyche butterfly and its host plant- Cardamine.
Cardamine plants are producing secondary metabolites - Glucosinolates which is an attractant. which attracts many pollinators like butterflies for pollinations.
when butterflies get attract towards plants having secondary metabolites- Glucosinolates ,female butterfly lay their eggs.

During egg stages, there are no harm to plants but when an egg hatched into caterpillar, Caterpilllar start eating leaves and this cause damage to the plants.

Due to damage of leaves eating by caterpillar, plants chemicals which is store in a specialised cells get mixed up(Glucosinolates and enzyme Myrosinase) which resulted into formation of new chemical (Isothiocyanates).
This new chemical (Isothiocyanates)act as protectant for plants from herbivores by acting as toxic for most of caterpillars of butterflies and other insects.

To overcome effect of toxic chemical (Isothiocyanates), caterpillar of Psyche butterflies evolved with proteins- NSP (Nitrile Specifier proteins) and MA(Major Allergens) which is helping to modify toxic chemical(Isothiocyanates) into non toxic chemicals(Nitrile).

This proteins work with enzymes Myrosinase. Due to mediators of proteins NSP and MA with enzymes Myrosinase, glucosinolates converts into Nitrile instead of Isothiocyanates.

Therefore, we dicussed reactions taking place in a Cardamine and Cleome plants, when plants get damaged.
Although, Cardamine plants (Brassicacae) and Cleome plants(Cleomaceae) beloging to different family but having same order- Brassicales which is known for production of chemicals- Glucosinolates and myrosinase enzymes.

Hence,In both Cardamine and Cleomeplants same reactions is taking place. i.e.
glucosinolates converts into Isothiocyanates(Toxic)with help of enzyme Myrosinase.

Whereas in gut of Psyche butterfly caterpillar, due to involvement of proteins- NSP and MA with enzyme Myrosinase, glucosinolates breakdown into Nitrile instead of Isothiocyanates.

we also refered below link to understand coevolution
Coevolution, or coevolution, is the reciprocal evolutionary change in a set of interacting populations over time resulting from the interactions between those populations. Usually, the interacting populations are different species, like plant–pollinator, predator–prey, or host–parasite.
Coevolution - an overview | ScienceDirect Topics.