16.4.2 Calmodulin-Like [CaM-Like]
Calmodulin-like (CML) activity is like a CaM-Ca
2+ sensor, but its functions are not
fully characterized (hence named calmodulin-like). CML contains 1 to 6 EF-hands,
but most of them are characterized having four EF-hands in the length of 83–330
residues. No functional motifs are identified in this protein (Snedden and Fromm
1998). In Arabidopsis thaliana (Vadassery et al. 2012a, b), Oryza sativa CML had
been reported. This sensor present in cytosol also grabs Ca
2+ ions. Some CMLs bind
with plasma membrane and modify lipid during membrane maintenance (Batistič
and Kudla 2012). CML11, CML12, CML16, CML17, and CML23 are highly
induced by elicitors of insect OS, which indicates their possible involvement in
defence against herbivore (Vadassery et al. 2012a, b). Among CMLs, 3 CMLs;
CML37, CML 42, and CML 43 are well known characterized during plant–herbivory interaction and for strengthening plant immunity against biotic stress.
CML 37 is highly upregulated during Spodoptera litura damage in Arabidopsis.
CML37 intermediates during signal cascade (Scholz et al. 2014). CML 37 and CML
42 work antagonistically to their function. CML 42 functions as a Ca
2+ sensor during
insect herbivory defence as well as during abiotic stress responses. CML 42 protein
is upregulated during biotic stresses and localizes to the cytosol and nucleus and
suppresses the plant defence mechanism. Jasmonic acid receptors negatively regulate its upregulation, which indicates that CML 42 connects Ca
2+ and jasmonic acid
signalling (Vadassery et al. 2012a). CML 42 is also involved in handling abiotic
stress response such as ultraviolet rays and drought stress. When Arabidopsis plant is
supplied with defence regulator, SA, CML 43 Ca
2+ sensor activity and
β-glucuronidase reporter activity are highly enhanced. This indicates that CML
43 actively functions as a plant immunity responser (Bender et al. 2014). CML9 is
not upregulated during herbivore S. littoralis attack and in response of spider mite
Tetranychus urticae. It is a specialized calcium sensor; it evokes SA-dependent
defence against phytopathogenic bacteria Pseudomonas syringae and fungus
Alternaria brassicicola independent of JA. It also involves in ion regulation during
drought response (Heyer et al. 2018; Leba et al. 2012). Zea mays induced responses
against Chilo partellus’s eggs were studied. It was found that it induces CML
312, CML442, CML159, and CML204 from maize genotype in order of attractiveness for defence against herbivore (Amanuel et al. 2020).
16.4.3 Calcineurins B-Like
Calcineurin B-like (CBL) is an important Ca
2+ sensor for land plants (Batistič and
Kudla 2009). CBL is similar to neuronal calcium sensor of animal (Luan et al. 2002;
Liu and Zhu 1998; Kudla et al. 1999). Once CBL interacts with Ca
2+ ions, they come
in contact with their regulatory Ser-Thr interacting protein kinase of SnRK3 subgroup and form a CBL-interacting protein kinase (CBL-CIPK) (CIPK) complex
which helps in deciphering Ca
2+ signals (Kim 2013; Zhu et al. 2013). In plants, CBL
present throughout the cell in plasma membrane, tonoplast, cytosol, and nucleus.
16 Role of Calcium Signalling During Plant–Herbivore Interaction
499
Calmodulin-like (CML) activity is like a CaM-Ca
2+ sensor, but its functions are not
fully characterized (hence named calmodulin-like). CML contains 1 to 6 EF-hands,
but most of them are characterized having four EF-hands in the length of 83–330
residues. No functional motifs are identified in this protein (Snedden and Fromm
1998). In Arabidopsis thaliana (Vadassery et al. 2012a, b), Oryza sativa CML had
been reported. This sensor present in cytosol also grabs Ca
2+ ions. Some CMLs bind
with plasma membrane and modify lipid during membrane maintenance (Batistič
and Kudla 2012). CML11, CML12, CML16, CML17, and CML23 are highly
induced by elicitors of insect OS, which indicates their possible involvement in
defence against herbivore (Vadassery et al. 2012a, b). Among CMLs, 3 CMLs;
CML37, CML 42, and CML 43 are well known characterized during plant–herbivory interaction and for strengthening plant immunity against biotic stress.
CML 37 is highly upregulated during Spodoptera litura damage in Arabidopsis.
CML37 intermediates during signal cascade (Scholz et al. 2014). CML 37 and CML
42 work antagonistically to their function. CML 42 functions as a Ca
2+ sensor during
insect herbivory defence as well as during abiotic stress responses. CML 42 protein
is upregulated during biotic stresses and localizes to the cytosol and nucleus and
suppresses the plant defence mechanism. Jasmonic acid receptors negatively regulate its upregulation, which indicates that CML 42 connects Ca
2+ and jasmonic acid
signalling (Vadassery et al. 2012a). CML 42 is also involved in handling abiotic
stress response such as ultraviolet rays and drought stress. When Arabidopsis plant is
supplied with defence regulator, SA, CML 43 Ca
2+ sensor activity and
β-glucuronidase reporter activity are highly enhanced. This indicates that CML
43 actively functions as a plant immunity responser (Bender et al. 2014). CML9 is
not upregulated during herbivore S. littoralis attack and in response of spider mite
Tetranychus urticae. It is a specialized calcium sensor; it evokes SA-dependent
defence against phytopathogenic bacteria Pseudomonas syringae and fungus
Alternaria brassicicola independent of JA. It also involves in ion regulation during
drought response (Heyer et al. 2018; Leba et al. 2012). Zea mays induced responses
against Chilo partellus’s eggs were studied. It was found that it induces CML
312, CML442, CML159, and CML204 from maize genotype in order of attractiveness for defence against herbivore (Amanuel et al. 2020).
16.4.3 Calcineurins B-Like
Calcineurin B-like (CBL) is an important Ca
2+ sensor for land plants (Batistič and
Kudla 2009). CBL is similar to neuronal calcium sensor of animal (Luan et al. 2002;
Liu and Zhu 1998; Kudla et al. 1999). Once CBL interacts with Ca
2+ ions, they come
in contact with their regulatory Ser-Thr interacting protein kinase of SnRK3 subgroup and form a CBL-interacting protein kinase (CBL-CIPK) (CIPK) complex
which helps in deciphering Ca
2+ signals (Kim 2013; Zhu et al. 2013). In plants, CBL
present throughout the cell in plasma membrane, tonoplast, cytosol, and nucleus.
16 Role of Calcium Signalling During Plant–Herbivore Interaction
499