[Structure and function of BmIntegrin β2 in silkworm, Bombyx mori]

Area of Science:

• Molecular Biology
• Immunology
• Cell Biology

Background:

• Integrins are transmembrane glycoproteins functioning as cell adhesion receptors and are vital in cellular signaling.
• Expressed on lepidopteran hemocytes, integrins play a key role in the insect immune response.
• Integrins form heterodimers, each composed of an alpha and a beta subunit.

Purpose of the Study:

• To identify and characterize the BmIntegrin β2 gene in lepidopteran species.
• To investigate the expression pattern of BmIntegrin β2 in different larval stages and tissues.
• To elucidate the role of BmIntegrin β2 in hemocyte adhesion and immune function.

Main Methods:

• Full-length cDNA sequence of BmIntegrin β2 was obtained using PCR and RACE.
• BmIntegrin β2 expression was analyzed via qRT-PCR in larval stages (L4D3, L5D3).
• A specific polyclonal antibody against BmIntegrin β2 was generated and validated using Western blotting; plasmatocyte adhesion assays were performed.

Main Results:

• The BmIntegrin β2 cDNA sequence is 2,434 bp, predicting a transmembrane protein.
• BmIntegrin β2 exhibited high expression in hemocytes and hematopoietic organs during late larval stages.
• The generated antibody specifically recognized BmIntegrin β2, and the protein was found to be critical for plasmatocyte adhesion and spreading.

Conclusions:

• BmIntegrin β2 is a transmembrane protein highly expressed in hemocytes and hematopoietic organs.
• BmIntegrin β2 is essential for the adhesion and spreading of plasmatocytes, indicating its significant role in cellular immunity.
• This research lays the groundwork for deeper investigations into the biological functions of BmIntegrin β2.