Saayoni Ghosh, key leader of the Trinamool Congress (TMC) Jadavpur MP, is learnt to have joined the rebel camp - a development that will be the biggest jolt to former West Bengal chief minister Mamata Banerjee amid her struggle to keep her party intact after the state election loss.Saayoni Ghosh represents Jadavpur constituency as an MP (X/@sayani06)Ghosh, who emerged as the most prominent voices against the Bharatiya Janata Party and a staunch Mamata Banerjee support during the campaign for the recently concluded West Bengal elections, is yet to confirm the move, though people familiar with the matter told HT she may already have picked a side and is part of the rebel group in what is emerging as the All India Trinamool Congress’s biggest crisis since its inception.A former Bengali actor, Saayoni Ghosh became politically prominent during recent Bengal election campaigns. She became associated with "Kaaba" and "Madina" because of a campaign speech/song in which she quoted or sang the line:“Mere dil mein hai Kaaba, aur mere aankhon mein Madina [Kaaba is in my heart, Madina in my eyes]," she had said. The line was used during an election rally to project communal harmony.This is the latest setback for Mamata Banerjee, TMC founder, who has been facing back-to-back blows from party leaders days after losing the elections. While 58 of party's total 80 MLAs, led by Ritabrata Banerjee, rebelled openly last week, staking claim to become the principal Opposition party in Bengal, MP Kakoli Ghosh on Monday offered support to the National Democratic Alliance (NDA) claiming that she has backing of 19 MPs — including Saayoni Ghosh, if speculation is to be believed.Ritabrata Banerjee was recognised as West Bengal’s leader of the opposition by the state assembly speaker last Wednesday.Meanwhile, Sushmita Dev resigned as Rajya Sabha MP and said she has quit the TMC, days after the resignation of Sukhendu Sekhar Ray from the Upper House.(with inputs from Saubhadra Chatterji)