SCIenTIfIC REPORTS | (2018) 8:3423 | DOI:10.1038/s41598-018-21598-1
Transcriptome changes induced by
abiotic stresses in Artemisia annua
, Ritesh Kumar
, Shubhra Rastogi
, Vikas Kumar Patel
, Alok Kalra
Madan Mohan Gupta
, Anil Kumar Gupta
& Ajit Kumar Shasany
Artemisia annua is known to be the source of artemisinin worldwide which is an antimalarial compound
but is synthesised in very limited amount in the plant. Most research laid emphasis on the methods of
enhancing artemisinin but our study has been planned in a way that it may simultaneously address two
problems encountered by the plant. Firstly, to know the eect on the artemisinin content in the era of
climate change because the secondary metabolites tend to increase under stress. Secondly, to identify
some of the stress responsive genes that could help in stress tolerance of the plant under abiotic stress.
Hence, the A. annua plants were subjected to four abiotic stresses (salt, cold, drought and water-
logging) and it was observed that the artemisinin content increased in all the stress conditions except
drought. Next, in order to identify the stress responsive genes, the transcriptome sequencing of the
plants under stress was carried out resulting in 89,362 transcripts for control and 81,328, 76,337, 90,470
and 96,493 transcripts for salt, cold, drought, and water logging stresses. This investigation provides
new insights for functional studies of genes involved in multiple abiotic stresses and potential candidate
genes for multiple stress tolerance in A. annua.
e stresses such as drought, salinity, chilling, freezing, water-logging, variable light conditions, nutrient starva-
tion and heat adversely aect the plant growth and productivity
. Plants undergo a series of physiological, mor-
phological, molecular and biochemical changes on encountering stress. Plants have a remarkable ability to cope
with the changing environmental conditions and try to adapt accordingly, depending upon the extent of stress
Numerous genes and biological pathways are known to be involved in abiotic stress tolerance in many plants,
and several others are thought to be involved
. Many genes and pathways are specic for a single type of stress
and several others show co-regulation in dierent stresses
. It has also been reported that when a plant is made
tolerant to one type of stress, it shows tolerance to some other stress also, indicating involvement of some com-
mon molecular mechanisms in dierent types of stresses
. Transcriptome sequencing and analysis is a reliable
and eort -saving method to understand the global molecular response of the stressed plants
which has been
reported in many plants for a single type of stress
, however only few reports are available for combination and/
or multiple stresses. In addition, there are limited studies on the impact of abiotic stresses on the medicinal plants.
Hence, the present investigation reports about the response of Artemisia annua plant against four abiotic stresses
(salt, cold, drought and water-logging/ooding).
A. annua L. belongs to Asteraceae family and is well known for its medicinal value to combat malaria
Artemisinin is the anti-malarial compound found in the plant which also possesses other activities like
anti-parasitic and anti-viral. e natural abundance of artemisinin in A. annua is very low (0.01–0.8%). Hence,
several strategies have been used to full the demand of high supply at a reduced rate
. Despite this, a limited
success has been achieved for obtaining artemisinin in vitro and we are still dependent on A. annua plants. e
artemisinin content of the plant depends on many parameters including the conditions like salinity stress, water
stress, chilling stress etc.
indicating that the stress related pathways and mechanisms somehow regulate the
artemisinin biosynthesis pathway also aecting the yield of artemisinin. As a result, it becomes desirable to get
a comprehension about the regulatory mechanisms involved in controlling artemisinin biosynthesis as well as
strategies and mechanisms for increasing the overall plant yield, oil content and trichome density in severe and
Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, P.O. CIMAP, Lucknow, 226015,
Department of Biochemistry, University of Lucknow, Lucknow, 226007, UP, India.
Division, CSIR-Central Institute of Medicinal and Aromatic Plants, P.O. CIMAP, Lucknow, 226015, UP, India.
Analytical Chemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, P.O. CIMAP, Lucknow,
226015, UP, India.
Genetics and Plant Breeding Division, CSIR-Central Institute of Medicinal and Aromatic Plants,
P.O. CIMAP, Lucknow, 226015, UP, India. Correspondence and requests for materials should be addressed to A.K.S.
Received: 25 May 2017
Accepted: 7 February 2018
Published: xx xx xxxx