*3.4. Expression Patterns of Eggplant Hsf and Hsp Genes*

To examine the heat response for *Hsfs* and *Hsps* in eggplant, an RNA sequencing profile (data not shown) in leaves of thermosensitive line 05-1 and thermotolerant line 05-4, at 0 and 6 h after HS treatment, was used. *Hsf* and *Hsp* genes were selected according to annotations and their expression profiles were analyzed. We analyzed the transcription levels of 18 *Hsf*, 25 *sHsp*, 6 *Hsp60*, 18 *Hsp70*, 11 *Hsp90* and 6 *Hsp100* genes in the leaves. As shown in Figure 3, for the thermosensitive line 05-1, 16 genes (89%) of the *Hsf* family were upregulated and two members, *SmHsfA4e* and *SmHsfB3*, were downregulated under HS conditions, which were more than in the thermotolerant line 05-4, in which 17 *Hsf* genes (94%) were upregulated by HS and only *SmHsfA8* was downregulated. In contrast to line 05-1, *SmHsfA4e* and *SmHsfB3* were strongly induced in treated 05-4 leaves. In the leaves of the thermotolerant line 05-4, among the upregulated members, the expression levels of most A (A1a, A1b, A3, A4a, A4b, A4d, A4e, A5, A6a and A6b), B1 and B2a were higher than those of other members under HS.

A strong response to HS in all of the 25 *sHsp* genes from both lines (05-1 and 05-4) was observed, in which a majority of these genes were upregulated and only *Sm15.6-sHsp* and *Sm15.8-sHsp* were downregulated. After high-temperature treatment, the expression of *SmHsp60-1*, *SmHsp60-2*, *SmCpn60-a2* and *SmCpn60-b3* was increased in the two inbred lines, while *SmHsp60-4* and *SmCpn60-b3* was increased in 05-4 and no significant difference could be observed in 05-1. Among the 18 *Hsp70* genes, the expression was remarkably changed in response to heat treatment in the thermosensitive 05-1 and thermotolerant

05-4 leaves and these genes were upregulated in both plants. Among these upregulated genes, the expression quantity of *SmHsp70-1*, *SmcpHsp70-2* and *SmHsp70-BIP4* was higher in 05-4, compared with 05-1. However, *SmHsp70-14* and *SmHsp70-15* were increased in the thermotolerant line, but decreased in the thermosensitive line. Considering the Hsp90 genes, the expression levels of most genes (*SmHsp90-1.3*, *SmHsp90-1.4*, *SmHsp90-1.5*, *SmHsp90-2.3*, *SmHsp90-5*, *SmHsp90-6*, *SmHsp9-7.1* and *SmHsp90-7.2*) were increased and only *SmHsp90-2.2* and *SmHsp90-4.3* were downregulated in the two lines. Among the upregulated *Hsp90* genes, gene expression levels of six genes in 05-4 were obviously higher than in 05-1. After heat treatment, *SmHsp100-ClpB1*, *SmHsp100-ClpB2*, *SmHsp100-ClpB3*, *SmHsp100-ClpD1* and *SmHsp100-ClpX2* expressions in the two lines were significantly increased. Among these genes, *SmHsp100-ClpB1*, *SmHsp100-ClpB3* and *SmHsp100-ClpX2* showed higher expression in 05-4 than in 05-1, but *SmHsp100-ClpB2* was more abundant in the thermosensitive line.
